The element hydrogen has the highest specific heat of all elements. At a temperature of 25°C, hydrogen’s specific heat capacity is 14300J/(kg K). If the temperature of a .34kg sample of hydrogen is to be raised by 25 K, how much heat will have to be transferred to the hydrogen?

Answers

Answer 1

Answer:

121550 J

Explanation:

Parameters given:

Mass, m = 0.34kg

Specific heat capacity, c = 14300 J/kgK

Change in temperature, ΔT = 25K

Heat gained/lost by an object is given as:

Q = mcΔT

Since ΔT is positive in this case and also because we're told that heat was transferred to the hydrogen sample, the hydrogen sample gained heat. Therefore, Q:

Q = 0.34 * 14300 * 25

Q = 121550J or 121.55 kJ


Related Questions

Say you have two parallel current-carrying wires, each carrying a current of 1.0 A and with a distance of 1.0 m between them. What is the magnitude of the force per unit length experienced by each wire

Answers

Answer:

[tex]\dfrac{F}{l}=2\times 10^{-7}\ N/m[/tex]

Explanation:

Given,

current in the wire I₁ = 1 A

                               I₂ = 1 A

distance between them, r = 1 m

using Force per unit length formula

[tex]\dfrac{F}{l}=\dfrac{\mu_0I_1I_2}{2\pi r}[/tex]

[tex]\mu_0 = magnetic\ permeability\ of\ free\ space = 4\pi\times 10^{-7}[/tex]

[tex]\dfrac{F}{l}=\dfrac{4\pi \times10^{-7}\times 1\times 1}{2\pi\times 1}[/tex]

[tex]\dfrac{F}{l}=2\times 10^{-7}\ N/m[/tex]

Hence, the magnitude of force per unit length is equal to [tex]\dfrac{F}{l}=2\times 10^{-7}\ N/m[/tex]

Final answer:

The magnitude of the force per unit length each 1.0 A current-carrying wire experiences when separated by a distance of 1.0 m is 2 x 10⁻⁷ N/m, calculated using the formula for magnetic force between parallel conductors.

Explanation:

When discussing two parallel current-carrying wires, we're addressing the magnetic force that arises between them due to their currents. Specifically, when each wire carries a current of 1.0 A and they are placed 1.0 m apart, the force per unit length that each wire experiences can be calculated using the formula for the magnetic force between two parallel conductors. The equation is FE = (µ0 / 2π) × (I1I2 / r), where µ0 is the magnetic constant (4π x 10-7 T·m/A), I1 and I2 are the currents in the wires, and r is the distance between the wires. Given that each wire carries 1.0 A of current and the separation is 1.0 m, we can plug these values into the formula to find that FE = (4π x 10-7 T·m/A / 2π) × (1.0 A2 / 1.0 m), resulting in a force per unit length of 2 x 10-7 N/m.

Singly charged positive ions are kept on a circular orbit in a cyclotron. The magnetic field inside the cyclotron is 1.833 T. The mass of the ions is 2.00×10-26 kg, and speed of the ions is 2.05 percent of the speed of the light. What is the diameter of the orbit? (The speed of the light is 3.00×108 m/s.)

Answers

Answer:

The diameter is  0.8376 m

Explanation:

Magnetic force is the force that is associated with the magnetic field, the magnitude of the magnitude force can be obtained using equation 1;

F = q v B  .....................................1,

where q is the magnitude of the charge of the particle =;

v is the  velocity and;

B is the magnetic field = 1.833 T ;

Here, the path of the charge is circular so the  force can be also considered as the centripetal force  which is represented in equation 2;

[tex]F_{c}[/tex] = m [tex]v^{2}[/tex] / r ....................................2,

m is the particle's mass = 2.00 x[tex]10^{-26}[/tex] kg

v is the speed of ion =  2.05% of 3.00 x [tex]10^{8}[/tex] = 0.0205 x 3.00 x [tex]10^{8}[/tex]

                                    = 6.15 x  [tex]10^{6}[/tex] m/s ;

Singly charged ion has a charge equal to the electron charge and the magnitude = 1.60217646 ×[tex]10^{-19}[/tex] C and;

r is the radius of the circular path.

to get  the diameter of the orbit  we equate equation 1 to 2 and isolate r in equation 2.

q v B = m [tex]v^{2}[/tex] / r

r = m v/q B.....................................3

r = (2.00 x[tex]10^{-26}[/tex] kg) x (6.15 x  [tex]10^{6}[/tex] m/s)  / (1.60217646 ×[tex]10^{-19}[/tex]  C) x (1.833 T)

r = 0.4188 m

The diameter is r x 2

D = 0.4188 m x 2

D = 0.8376 m

Therefore the diameter is  0.8376

A particle of mass m is confined to a box of length`. Its initial wave function is identical to that of the displacement of the string in the problem above, Boas Ch. 13, Sec. 4, #4.Find the solution of the Schrodinger equation

Answers

Answer:

 φ = √2/L sin (kx),   E = (h² / 8 mL²) n²  

Explanation:

The Schrödinger equation for a particle in a box is, described by a particle within a potential for simplicity with infinite barrier

      V (x) =   ∞            x <0

                    0      0 <x <L

                    ∞           x> L

This means that we have a box of length L

We write the equation

              (- h’² /2m  d² / dx² + V) φ = E φ

             h’= h / 2π

The region of interest is inside the box, since being the infinite potential there can be no solutions outside the box. The potential is zero

                - h’² /2m d²φ/ dx² = E φ

The solution for this equation is a sine wave,

Because it is easier to work with exponentials, let's use the reaction between the sine function and cook with the exponential

               [tex]e^{ikx}[/tex] = cos kx + i sin kx

Let's make derivatives

              dφ / dx = ika e^{ikx}

              d²φ / dx² = (ik) e^{ikx} = - k² e^{ikx}

             

Let's replace

            - h'² / 2m (-k² e^{ikx}) = E e^{ikx}

            E = h'² / 2m    k²

To have a solution this expression

Now let's work on the wave function, as it is a second degree differential bond, two solutions must be taken

             φ = A e^{ikx} + B e^{-ikx}

This is a wave that moves to the right and the other to the left.

Let's impose border conditions

         φ (0) = 0

         φ (L) = 0

For being the infinite potential

With the first border condition

         0 = A + B

         A = -B

They are the second condition

         0 = A e^{ikL}+ B e^{-ikL}

We replace

        0 = A (e^{ikL} - e^{-ikL})

We multiply and divide by 2i, to use the relationship

        sin kx = (e^{ikx} - e^{-ikx}) / i2

        0 = A 2i sin kL

             

Therefore kL = nπ

         k = nπ / L

The solution remains

         φ = A sin (kx)

        E = (h² / 8 mL²) n²

To find the constant A we must normalize the wave function

       φ*φ = 1

       A² ∫ sin² kx dx = 1

             

We change the variable

       sin² kx = ½ (1 - cos 2kx)

       A =√ 2 / L

The definitive function is

          φ = √2/L sin (kx)

What are (a) the x component and (b) the y component of a vector in the xy plane if its direction is 259° counterclockwise from the positive direction of the x axis and its magnitude is 5.4 m?

Answers

Answer:

|Ax| =1.03 m  (directed towards negative x-axis)

|Ay|= 5.30 (directed towards negative y-axis)

Explanation:

Let A is a vector = 5.4 m

θ = 259°

to Find Ax, Ay

Sol:

according the condition it lies in 3rd quadrant

we know that Horizontal Component Ax = A cos θ

Ax = 5.4 Cos 259°

Ax = - 1.03 m

|Ax| =1.03 m  (directed towards negative x-axis)

Now Ay = A sin θ

Ay = 5.4 Sin 259°

Ay = -5.30

|Ay|= 5.30 (directed towards negative y-axis)

Answer:

(a) -1.030m

(b) -5.301m

Explanation:

Given a vector F in the xy plane, of magnitude F and in a direction θ counterclockwise from the positive direction of the x-axis;

The x-component ([tex]F_{X}[/tex]) of vector F is given by;

[tex]F_{X}[/tex] = F cos θ    ---------------------(i)

And;

The y-component ([tex]F_{Y}[/tex]) of vector F is given by;

[tex]F_{Y}[/tex] = F sin θ            -----------------------(ii)

Now to the question;

Let the vector be A

Therefore;

The magnitude of vector A is A = 5.4m

The direction θ of A counterclockwise from the positive direction of the x-axis = 259°

(a) The x-component ([tex]A_{X}[/tex]) of the vector A is therefore given by;

[tex]A_{X}[/tex] = A cos θ       ------------------------(iii)

Substitute the values of θ and A into equation (iii) as follows;

[tex]A_{X}[/tex] = 5.4 cos 259°

[tex]A_{X}[/tex] = 5.4 x (-0.1908)

[tex]A_{X}[/tex] = -1.030

Therefore, the x-component of the vector is -1.030m

(b) The y-component ([tex]A_{Y}[/tex]) of the vector A is therefore given by;

[tex]A_{Y}[/tex] = A sin θ       ------------------------(iv)

Substitute the values of θ and A into equation (iv) as follows;

[tex]A_{Y}[/tex] = 5.4 sin 259°

[tex]A_{Y}[/tex] = 5.4 x (-0.9816)

[tex]A_{Y}[/tex] = -5.301m

Therefore, the y-component of the vector is -5.301m

Describe what changes you would expect to see in a plot of absorbance versus temperature in an optical melting experiment on a self-complementary duplex.

Answers

Answer:

#Check explanation below for a detailed description.

Explanation:

A plot of absorbance vs temperature is used to determine  [tex]T_m[/tex] of a duplex DNA.

-The duplex DNA denatures.

-The denaturation creates two single strands which enhances Ultraviolet absorption ( increased temperatures increases absorption rates).

-Higher concentrations of [tex]Sodium \ Chloride[/tex] hampers stability of the DNA.

A truck runs into a pile of sand, moving 0.80 m as it slows to a stop. The magnitude of the work that the sand does on the truck is 5.5×105J. Part A Determine the magnitude of the average force that the sand exerts on the truck

Answers

Answer:

687,500 N

Explanation:

Workdone = Force × Distance

Making force the subject of the formula; we have:

Force =[tex]\frac{workdone}{distance}[/tex]

Given that:

workdone  = 5.5×10⁵ J

Distance = 0.80 m

∴ Force = [tex]\frac{5.5*10^5}{0.8}[/tex]

Force = 687,500 N

Answer:

6.875×10⁵  N.

Explanation:

Force: This can be defined as the product of mass and acceleration or it can be defined as the ratio of work done and distance. The S.I unit of force is Newton.

W = F×d................. Equation 1

Where W = work done, F = force, d = distance.

make F the subject of the equation

F = W/d.................... Equation 2

Given: W = 5.5×10⁵ J, d = 0.8 m

Substitute into equation 2

F =  5.5×10⁵ /0.8

F = 6.875×10⁵  N.

Hence the force exerted on the truck by the sand = 6.875×10⁵  N.

Cylinder A has a mass of 2kg and cylinder B has a mass of 10kg. Determinethe velocity of A after it has displaced 2m from its original starting position. Neglect the mass of the cable and pulleys and assume that both cylinders start at res

Answers

The velocity of A is 5.16m/s²

Explanation:

Given-

mass of cylinder A, mₐ = 2kg

mass of cylinder B, mb = 10kg

Distance, s = 2m

Velocity of A, v = ?

Let acceleration due to gravity, g = 10m/s²

We know,

[tex]a = \frac{mb * g - ma * g}{ma + mb} \\\\a = \frac{10 * 10 - 2 * 10}{ 2 + 10} \\\\a = \frac{80}{12} \\\\a = 6.67m/s^2[/tex]

We know,

[tex]v = \sqrt{2as}[/tex]

[tex]v = \sqrt{2 X 6.67 X 2} \\\\v = \sqrt{26.68} \\\\v = 5.16m/s^2[/tex]

Therefore, the velocity of A is 5.16m/s²

g Case 1, a mass M M hangs from a vertical spring having spring constant k , k, and is at rest at its equilibrium height. In Case 2, the same mass has been lifted a distance D D vertically upward. If the potential energy in Case 1 is defined to be zero, what is the potential energy in Case 2

Answers

Final answer:

In the scenario described, increasing the height of a mass M in a vertical spring-mass system will result in both gravitational and spring potential energy. Thus, the potential energy in Case 2 is the sum of gravitational potential energy (m*g*D) and the elastic potential energy of the spring (1/2*k*D^2).

Explanation:

The situation described in the question deals with principles of Physics, specifically potential energy and its application to the spring-mass system. Consider both cases with the mass M hanging from a spring with a constant k in a vertical orientation. In the first case, the system is at equilibrium and thus the potential energy is defined as zero.

In the second case, the mass M is lifted upward a vertical distance D from the equilibrium position, it now possesses gravitational potential energy in addition to the elastic potential energy of the spring. This total energy is preserved as long as no external force behaves on the system. The gravitational potential energy gained by the mass is equal to m*g*D where m is the mass, g is the acceleration due to gravity and D is the vertical distance lifted.

The potential energy stored in the spring when it is stretched or compressed by a distance 'x' is given by the formula U = 1/2*k*x^2, where 'k' is the spring constant and 'x' is the displacement from the equilibrium position (in this case is D).

So, combining both energies, the total potential energy in Case 2, when the mass has been lifted a vertical distance D is m*g*D + 1/2*k*D^2.

Learn more about Potential Energy here:

https://brainly.com/question/24284560

#SPJ12

The driving force for fluid flow is the pressure difference, and a pump operates by raising the pressure of a fluid (by converting the mechanical shaft work to flow energy). A gasoline pump is measured to consume 3.8 kW of electric power when operating, If the pressure differential between-the outlet and inlet of the pump is measured to be 7 kPa and the changes in velocity and elevation are negligible, determine the maximum possible volume flow rate of gasoline.

Answers

Answer:

[tex]\dot V = 0.542 \frac{m^{3}}{s}[/tex]

Explanation:

The power needed for the pump to raise the pressure of gasoline is defined by following equation. The maximum possible volume flow rate is isolated and then calculated:

[tex]\dot W = \dot V \cdot \Delta P\\\dot V = \frac{\dot W}{\Delta P}\\\dot V = \frac{3.8 kW}{7 kPa}\\\dot V = 0.542 \frac{m^{3}}{s}[/tex]

Explanation:

Below is an attachment containing the solution.

A factory worker pushes a crate of mass 31.0 kg a distance of 4.35 m along a level floor at constant velocity by pushing horizontally on it. The coefficient of kinetic friction between the crate and floor is 0.26.

a. What magnitude of force must the worker apply?
b. How much work is done on the crate by this force?
c. How much work is done on the crate by friction?
d. How much work is done on the crate by the normal force? By gravity?
e. What is the total work done on the crate?

Answers

Answer:

a. 79.1 N

b. 344 J

c. 344 J

d. 0 J

e. 0 J

Explanation:

a. Since the crate has a constant velocity, its net force must be 0 according to Newton's 1st law. The push force [tex]F_p[/tex] by the worker must be equal to the friction force [tex]F_f[/tex] on the crate, which is the product of friction coefficient μ and normal force N:

Let g = 9.81 m/s2

[tex]F_p = F_f = \mu N = \mu mg = 0.26 * 31 * 9.81 = 79.1 N[/tex]

b. The work is done on the crate by this force is the product of its force [tex]F_p[/tex] and the distance traveled s = 4.35

[tex]W_p = F_ps = 79.1*4.35 = 344 J[/tex]

c. The work is done on the crate by friction force is also the product of friction force and the distance traveled s = 4.35

[tex]W_f = F_fs = -79.1*4.35 = -344 J[/tex]

This work is negative because the friction vector is in the opposite direction with the distance vector

d. As both the normal force and gravity are perpendicular to the distance vector, the work done by those forces is 0. In other words, these forces do not make any work.

e. The total work done on the crate would be sum of the work done by the pushing force and the work done by friction

[tex]W_p + W_f = 344 - 344 = 0 J[/tex]

Answer:

(A) 79N

(B) W = 344J

(C) Wf= -344J

(D) W = 0J

(E) W = 0J

Explanation:

Please see attachment below.

What is the voltage across six 1.5-V batteries when they are connected (a) in series, (b) in parallel, (c) three in parallel with one another and this combination wired in series with the remaining three?

Answers

Final answer:

The resultant voltage depends on the arrangement of the batteries. For series configuration, the voltage sums up to 9V. For parallel, it remains 1.5V. And for combined series and parallel, it sums up to 3V.

Explanation:

The voltage across batteries depends on how they are connected.

 When the batteries are connected in series, the voltages add up. So, for six 1.5-V batteries, the total voltage is 6 * 1.5V = 9V. When the batteries are connected in parallel, the voltage remains the same as one battery, which is 1.5V, no matter how many batteries are connected. If three batteries are connected in parallel with each other and then in series with the remaining three also organized in parallel, the voltage would be 1.5V (parallel group) + 1.5V (parallel group) = 3V.

Learn more about Voltage here:

https://brainly.com/question/31347497

#SPJ3

A small sphere is at rest at the top of a frictionless semicylindrical surface. The sphere is given a slight nudge to the right so that it slides along the surface. Let R = 1.45 ft and let the angle at which the sphere separates from the cylinder be θs = 34°. The sphere was placed in motion at the very top of the cylinder. Determine the sphare;s initial speed.

Answers

Answer:

vi = 4.77 ft/s

Explanation:

Given:

- The radius of the surface R = 1.45 ft

- The Angle at which the the sphere leaves

- Initial velocity vi

- Final velocity vf

Find:

Determine the sphere's initial speed.

Solution:

- Newton's second law of motion in centripetal direction is given as:

                         m*g*cos(θ) - N = m*v^2 / R

Where, m: mass of sphere

             g: Gravitational Acceleration

             θ: Angle with the vertical

             N: Normal contact force.

- The sphere leaves surface at θ = 34°. The Normal contact is N = 0. Then we have:

                         m*g*cos(θ) - 0 = m*vf^2 / R

                         g*cos(θ) = vf^2 / R    

                         vf^2 = R*g*cos(θ)

                         vf^2 = 1.45*32.2*cos(34)

                        vf^2 = 38.708 ft/s

- Using conservation of energy for initial release point and point where sphere leaves cylinder:

                          ΔK.E = ΔP.E

                          0.5*m* ( vf^2 - vi^2 ) = m*g*(R - R*cos(θ))

                          ( vf^2 - vi^2 ) = 2*g*R*( 1 - cos(θ))

                          vi^2 =  vf^2 - 2*g*R*( 1 - cos(θ))

                          vi^2 = 38.708 - 2*32.2*1.45*(1-cos(34))

                          vi^2 = 22.744

                           vi = 4.77 ft/s

The potential difference between a pair of oppositely charged parallel plates is 398 V. If the spacing between the plates is doubled without altering the charge on the plates, what is the new potential difference between the plates? Answer in units of V.

Answers

Answer:

Explanation:

capacitance of parallel plate capacitor

c = ε A / d , d is distance between plates , A is surface area , ε is constant

As d becomes two times , Capacitance c = 1/ 2 times ie c / 2

potential V = Q / C

Q is constant , potential

v = Q / c /2

= 2 . Q / C

= 2 V

So potential difference becomes 2 times.

NEW P D = 398 X 2

= 796 V.

A beam of electrons is accelerated from rest through a potential difference of 0.200 kV and then passes through a thin slit. When viewed far from the slit, the diffracted beam shows its first diffraction minima at ± 13.6 ∘ from the original direction of the beam.

Do we need to use relativity formulas? Select the correct answer and explanation.

a. No. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=mc2/(γ−1). The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is0.511 MeV, we have γ–1=(0.511MeV)/(0.200keV) so γ−1>>1 which means that we do not have to use special relativity.
b. Yes. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=(γ−1)mc2. The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is0.511 MeV, we have γ–1=(0.200keV)/(0.511MeV) so γ<<1 which means that we have to use special relativity.
c. Yes. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=mc2/(γ−1). The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is0.511 MeV, we have γ–1=(0.511MeV)/(0.200keV) so γ>>1 which means that we have to use special relativity.
d. No. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=(γ−1)mc2. The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is 0.511 MeV, we have γ–1=(0.200keV)/(0.511MeV) so γ−1<<1 which means that we do not have to use special relativity.

Part B

How wide is the slit?

Answers

Final answer:

Option d is correct; relativity formulas are not needed because the Lorentz factor (γ-1) is much less than 1, indicating that the electron's velocity is non-relativistic after being accelerated through a potential difference of 0.200 kV.

Explanation:

We need to determine whether we should use relativity formulas for the electrons accelerated through a potential difference. When electrons gain kinetic energy (K) by acceleration through a potential difference (V), the energy they gain can be expressed as Ve=K=(γ-1)mc2. Here, γ stands for Lorentz factor, m is the mass of electron, and c is the speed of light. Given that the potential difference ('V') is 0.200 kV, and the rest mass energy ('Eo') of an electron is 0.511 MeV, we calculate:

γ-1= (0.200 keV) / (0.511 MeV) ≈ 0.3916 × 10-3, which implies that γ is approximately 1. So, γ-1 << 1, which in turn means that the electron's velocity is much less than the speed of light, and the relativistic effect can be neglected. Thus, we do not need to use special relativity.

The correct answer is d.

If a trapeze artist rotates 1 each second while sailing through the air, and contracts to reduce her rotational inertia to 0.40 of what it was, how many rotations per second will result?

Answers

Thus the number of rotations per second are 2.5

Explanation:

A trapeze is rotating with 1 rotation per second .

Thus its angular velocity ω = 2π n

here n is the number of rotations per second

Thus ω = 2π b because n = 1 in this case

Suppose the moment of inertia of his is = I

Then angular momentum L₁ = I  ω = 2 I π

In the second case , the moment of inertia becomes = 0.4 I

Let his angular velocity is  ω₀

Thus angular momentum L₂ = 0.4 I  ω₀

Because no external torque is applied , therefore angular momentum will remain constant .

Thus L₁ = L₂

Therefore  2 I π = 0.4 I x 2 n₀ π

here n₀ is the number of rotations per second

n₀ = [tex]\frac{1}{0.4}[/tex] = [tex]\frac{5}{2}[/tex] = 2.5

A remote-controlled car’s wheel accelerates at 22.7 rad/s2 . If the wheel begins with an angular speed of 10.3 rad/s, what is the wheel’s angular speed after exactly twenty full turns

Answers

Explanation:

Below is an attachment containing the solution.

A 62.0 kg skier is moving at 6.90 m/s on a frictionless, horizontal, snow-covered plateau when she encounters a rough patch 4.50 m long. The coefficient of kinetic friction between this patch and her skis is 0.300. After crossing the rough patch and returning to friction-free snow, she skis down an icy, frictionless hill 2.50 m high.

How fast is the skier moving when she gets to the bottom ofthe hill?

Answers

Final answer:

The skier is moving at 11.1 m/s when she gets to the bottom of the hill. This solution is derived using the principles of energy conservation and work done by friction.

Explanation:

A 62.0 kg skier is moving at 6.90 m/s on a frictionless, horizontal, snow-covered plateau when she encounters a rough patch 4.50 m long. The coefficient of kinetic friction between this patch and her skis is 0.300. After crossing the rough patch and returning to friction-free snow, she skis down an icy, frictionless hill 2.50 m high. To determine how fast the skier is moving when she gets to the bottom of the hill, we analyze the problem using principles of energy conservation and work done by friction.

We start with the equation that equates the final kinetic and potential energies to the initial energies along with the work done by friction. This equation is 0.5 mv² + 0 = 0.5 mu² + μmgl + mgh, where v is the final velocity, μ is the coefficient of friction, g is the acceleration due to gravity (9.8 m/s²), l is the length of the rough patch, and h is the height of the hill.

Plugging in the given values,

we have: 0.5 v² = 0.5 x 6.9 x 6.9 + 0.3 x 9.8 x 4.5 + 9.8 x 2.50. S

implifying, we get v² = 123.07, which leads to v = 11.1 m/s.

Thus, the skier's speed at the bottom of the hill is 11.1 m/s.

Two 3.0 μC charges lie on the x-axis, one at the origin and the other at What is the potential (relative to infinity) due to these charges at a point at on the x-axis?

Answers

Complete Question:

Two 3.0µC charges lie on the x-axis, one at the origin and the other at 2.0m. A third point is located at 6.0m. What is the potential at this third point relative to infinity? (The value of k is 9.0*10^9 N.m^2/C^2)

Answer:

The potential due to these charges is 11250 V

Explanation:

Potential V is given as;

[tex]V =\frac{Kq}{r}[/tex]

where;

K is coulomb's constant = 9x10⁹ N.m²/C²

r is the distance of the charge

q is the magnitude of the charge

The first charge located at the origin, is 6.0 m from the third charge; the potential at this point is:

[tex]V =\frac{9X10^9 X3X10^{-6}}{6} =4500 V[/tex]

The second charge located at 2.0 m, is 4.0 m from the third charge; the potential at this point is:

[tex]V =\frac{9X10^9 X3X10^{-6}}{4} =6750 V[/tex]

Total potential due to this charges  = 4500 V + 6750 V = 11250 V

Final answer:

The potential due to two 3.0 μC charges on the x-axis at different distances from a point can be calculated using Coulomb's Law.

Explanation:

The potential due to two point charges can be found using Coulomb's Law. The potential, V, at a point on the x-axis is the sum of the potentials from each charge. The potential due to a point charge can be calculated using the formula V = k * (Q / r), where k is the electrostatic constant, 9 x 10^9 Nm^2/C^2, Q is the charge, and r is the distance between the charge and the point. In this case, since the charges are on the x-axis, the distance between the origin and the point is x, and the distance between the other charge and the point is (6-x). So, the potential at the point is V = k * (3.0 x 10^-6 / x) + k * (3.0 x 10^-6 / (6-x)) relative to infinity.

Learn more about potential here:

https://brainly.com/question/28300184

#SPJ3

An ideal gas Carnot cycle with air in a piston cylinder has a high temperature of 1000 K and a heat rejection at 400 K. During the heat addition the volume triples. Find the two specific heat transfers (q) in the cycle and the overall cycle efficiency

Answers

Answer:

W / n = - 9133 J / mol, W / n = 3653 J / mol , e = 0.600

Explanation:

The Carnot cycle is described by

      [tex]e= 1 - Q_{c} / Q_{H} = 1 - T_{c} / T_{H}[/tex]

     

In this case they indicate that the final volume is

         V = 3V₀

In the part of the heat absorption cycle from the source is an isothermal expansion

         W = n RT ln (V₀ / V)

         W / n = 8.314 1000 ln (1/3)

          W / n = - 9133 J / mol

During the part of the isothermal compression in contact with the cold focus, as in a machine the relation of volumes is maintained in this part is compressed three times

            W / n = 8.314 400 (3)

           W / n = 3653 J / mol

The efficiency of the cycle is

            e = 1- 400/1000

            e = 0.600

The op amp in this circuit is ideal. R3 has a maximum value of 100 kΩ and σ is restricted to the range of 0.2 ≤ σ ≤ 1.0. a. Calculate the range of vO if vI = 40 mV. b. If σ is not restricted, at what value of σ will the operational amplifier saturate?

Answers

I have attached the circuit image missing in the question.

Answer:

A) The range of vo is; -6.6V≤ vo ≤-1V

B) σ = 0.1861

Explanation:

A) First of all, Let VΔ be the voltage from the potentiometer contact to the ground.

Thus; [(0 - vg)/(2000)] +[(0 - vΔ)/(50,000)] = 0

So, [(- vg)/(2000)] +[(- vΔ)/(50,000)] = 0

Simplifying further; -25 vg - vΔ = 0

From the question, vg = 40mV = 0.04 V

So - 25(0.04) = vΔ

So: vΔ = - 1 V

Now, [vΔ/(σRΔ)] + [(vΔ - 0)/(50,000)] + [(vΔ - vo)/((1 - σ)RΔ))] = 0

So, multiplying each term by RΔ to get; [vΔ/(σ)] + [(vΔ x RΔ)/(50,000)] + [(vΔ - vo)/((1 - σ))] = 0

So RΔ = 100kΩ or 100,000Ω from the question.

So, substituting for RΔ, we get,

[vΔ/(σ)] + [2vΔ] + [(vΔ - vo)/((1 - σ))] = 0

Let's put the value of - 1 for vΔ as gotten before.

So, ( - 1/σ) - 2 + [(-1 - vo)/(1 - σ)] = 0

Now let's make vo the subject of the equation to get;

-1 - vo = (1 - σ)[2 + (1/σ)]

-1 - vo = 2 - 2σ + (1/σ) - 1

-vo = 1 + 2 - 2σ + (1/σ) - 1

-vo = 2 - 2σ + (1/σ)

vo = - 1 (2 - 2σ + (1/σ))

When σ = 0.2; vo = - 1(2 - 0.4 + 5) =

- 1 x 6.6 = - 6.6V

Also when σ = 1;

vo = - 1(2 - 2 + 1) = - 1V

Therefore, the range of vo is;

- 6.6V ≤ vo ≤ - 1V

B) it will saturate at vo = - 7V

So, from;

vo = - 1 (2 - 2σ + (1/σ))

-7 = - 1 (2 - 2σ + (1/σ))

Divide both sides by (-1)

7 = (2 - 2σ + (1/σ))

Now, subtract 2 from both sides to get; 5 = - 2σ + (1/σ)

Multiply each term by α to get;

5σ = - 2σ^(2) + 1

So 2σ^(2) + 5σ - 1 = 0

Solving simultaneously and picking the positive value , we get σ to be approximately 0.1861

Final answer:

The question involves understanding an ideal operational amplifier's output behavior, focusing on its output voltage changes and saturation with respect to variations in σ (sigma). Calculations for the output voltage range given a specific input and understanding the conditions under which the op-amp will saturate are key.

Explanation:

The question revolves around an operational amplifier (op-amp) circuit, exploring its behavior under certain conditions, specifically examining output voltage (vO) variations and saturation point related to the parameter σ (sigma). The op-amp is assumed to be ideal, implying infinite gain, zero input current, and that its input terminals are at the same potential.

a. Range of vO if vI = 40 mV

Given that the op-amp is ideal, the output voltage will depend on the input voltage (vI), the gain settings (σ), and the feedback resistor (R3). In practical scenarios, the gain can be adjusted by changing the value of σ or R3. However, for an ideal op-amp, the input voltage is directly proportional to the output voltage, influenced by σ. With vI = 40 mV and σ ranging between 0.2 and 1.0, the output voltage will vary accordingly, directly proportional to these parameters.

b. Saturation point of the op-amp

Saturation in an op-amp occurs when the output voltage exceeds the power supply limits, meaning the op-amp can no longer amplify the input signal. The specific value of σ at which saturation occurs depends on the supply voltage, the op-amp's maximum output voltage capability, and the configuration of the feedback network. Without specific values for the power supply or feedback network, calculating the exact σ value for saturation is not possible. Yet, in theory, as σ approaches the op-amp's gain limit or if the gain results in an output voltage beyond what the op-amp can deliver based on its power supply, saturation will occur.

Three individual point charges are placed at the following positions in the x-y plane:Q3= 5.0 nC at (x, y) = (0,0);Q2= -3.0 nC at (x, y) = (4 cm, 0); and Q1= ?nC at (x, y) = (2 cm,0);What isthe magnitude, and sign, ofcharge Q1such that the net force exerted on charge Q3, exerted bycharges Q1and Q2, is zero?

Answers

Answer:

Explanation:

net force exerted on charge Q₃, exerted by charges Q₁and Q₂, will be  zero

if net  electric field due to charges Q₁ and Q₂  at origin is zero .

electric field due to Q₂

= 9 X 10⁹ X 3 x10⁹ / .04²

electric field due to Q₁

= 9 X 10⁹ X Q₁ / .02²

For equilibrium

9 X 10⁹ X Q₁ / .02² = 9 X 10⁹ X 3 x10⁻⁹ / .04²

Q₁  = 3 X10⁻⁹ x .02² / .04²

= 3 / 4 x 10⁻⁹

.75 x 10⁻⁹  C

If the frequency of the radio station is 88.1MHz(8.81 •10^7Hz), what is the wavelength of the wave used by the radio station for its broadcast? The answer should have three significant figures

Answers

Answer:

3.41m

Explanation:

The following were obtained from the question:

f (frequency) = 8.81x10^7Hz

V (velocity of electromagnetic wave) = 3x10^8 m/s

λ (wavelength) =?

Velocity, frequency and wavelength of a wave are related with the equation below:

V = λf

λ = V/f

λ = 3x10^8 /8.81x10^7

λ = 3.41m

Therefore, the wavelength of the radio wave is 3.41m

Answer:

Answer: 3.41

Explanation:

Edge 2020 (E2020)

Analyzing the Light Bulb: You should have noticed that the light bulb doesn't have a single well-defined "resistance," since the current vs. voltage plot is nonlinear. Nevertheless, one can define a "voltage-dependent resistance" as R(V)=V/I(V)as the ratio of voltage to current.1Basic Behavior: According to your data, does this resistance increase or decrease with voltage? A reasonable (and correct) thought is that the impact is really with temperature, as the light bulb heats up with more power going into it. How does your data imply resistance varies with temperature?Thermal Expansion: One hypothesis you might have is that the reason is that the resistor expands slightly with increased temperature (since most materials do), and hence the cross-sectional area and length of the resistor change.Supposing the resistor increases in size by the same factor in every direction, what direction does the resistance change? (I.e., does the resistance get larger or smaller?) Is this the direction that you expect based on your answer to the previous part?

Answers

Answer:

Resistance increases with increase in temperature which depends on power supplied which also depends on voltage.

Thermal expansion will make resistance larger.

Explanation:

Light bulb is a good example of a filament lamp. If we plot the graph of voltage against current we will notice that resistance is constant at constant temperature.

The filament heats up when an electric current passes through it, and produces light as a result.

The resistance of a lamp increases as the temperature of its filament increases. The current flowing through a filament lamp is not directly proportional to the voltage across it.

tensile stress begins to appear in resistor as the temperature rises. Thus, the resistance value increases as the temperature rises. Resistance value can only decrease as the temperature rises in case of thin film resistor with aluminium substrate.

In case of a filament bulb, the resistance will increase as increase in length of the wire. The thermal expansion in this regard is linear expansivity in which resistance is proportional to length of the wire.

Resistance therefore get larger.

What determines whether the equilibrium temperature of a mixture of two amounts of water will be closer to the initially cooler or warmer water?

Answers

Final answer:

The equilibrium temperature of a mixture of two amounts of water will be closer to the initially cooler water due to the specific heat capacity of water.

Explanation:

The equilibrium temperature of a mixture of two amounts of water will be closer to the initially cooler water.

When different temperatures of water are mixed, heat is transferred between them until they reach a common equilibrium temperature. The amount of heat transferred is determined by the specific heat capacity of water, which is greater than most common substances. As a result, water undergoes a smaller temperature change for a given heat transfer. Therefore, the equilibrium temperature will be closer to the initially cooler water.

An airplane is flying horizontally with a speed of 103 km/hr (278 m/s) when it drops a payload. The payload hits the ground 30 s later. (Neglect air drag and the curvature of the Earth. Take g = 10 m/s².)
At what altitude H is the airplane flying?

Answers

Answer:

H = 4500 m

Explanation:

Once dropped, the payload moves along a trajectory, that can be decomposed along two directions independent each other.Just by convenience, we choose these directions to be coincident with the horizontal (-x) and vertical (y) axes.As both movements are independent each other due to both are perpendicular, in the vertical direction, the initial speed is 0.So, in order  to find the vertical displacement at any point in time, we can use the following kinematic equation, where a=-g., and H = -Δy.

        [tex]H = \frac{1}{2}*g*t^{2} = \frac{1}{2} * 10 m/s2*(30s)^{2} = 4500 m[/tex]

The airpane was flying at a 4500 m altitude.

You are generating traveling waves on a stretched string by wiggling one end. If you suddenly begin to wiggle more rapidly without appreciably affecting the tension, you will cause the waves to move down the string a. faster than before.b. at the same speed as before.c. slower than before.

Answers

Answer:

Option as B is correct At the same speed as before

Explanation:

As we know the relation between speed of the wave and tension in string

The speed of wave in stretched string

ν = [tex]\sqrt{\frac{T}{\mu} }[/tex]  

speed of wave is the directly proportional to the square root of tension as mentioned in question tension of string is unaffected when in linear mass density is constant,  so we can say that the  speed of wave will  be the same  

Option as B is correct At the same speed as before  

If you suddenly begin to wiggle more rapidly without appreciably affecting the tension, you will cause the waves to move down the string at the same speed as before (Option b).

What is a wave?

A wave can be defined as a type of disturbance that contains energy independently of particle motion.

The wave can move at a velocity (frequency) that is directly proportional to the tension.

In this case, tension is constant, thereby velocity of the wave will remain constant.  

In conclusion, if you suddenly begin to wiggle more rapidly without appreciably affecting the tension, you will cause the waves to move down the string at the same speed as before (Option b).

Learn more in:

https://brainly.com/question/12215474

A 20.0-kg cannonball is fired from a cannon with muzzle speed of 1 000 m/s at an angle of 37.08 with the horizontal. A second ball is fired at an angle of 90.08. Use the isolated system model to find (a) the maximum height reached by each ball and (b) the total mechanical energy of the ball–Earth system at the maximum height for each ball. Let y5 0 at the cannon.

Answers

Answer:

(a). The maximum height by first ball is [tex]1.8545\times10^{4}\ m[/tex]

The maximum height by second ball is [tex]5.1020\times10^{4}\ m[/tex]

(b). The total mechanical energy of the ball–Earth system at the maximum height for each ball is [tex]1.0\times10^{7}\ J[/tex]

Explanation:

Given that,

Mass of cannonball = 20.0 kg

Speed = 1000 m/s

Angle with horizontal= 37.08

Fired angle = 90.08

We need to calculate the speed of the ball

Using formula of speed

[tex]v_{y}=v\sin\theta_{H}[/tex]

Put the value into the formula

[tex]v_{y}=1000\times\sin37.08[/tex]

[tex]v_{y}=602.9\ m/s[/tex]

(a). We need to calculate the maximum height by first ball

Using conservation of energy

[tex]\dfrac{1}{2}mv^2=mgh[/tex]

[tex]h= \dfrac{v^2}{2g}[/tex]

Put the value into the formula

[tex]h=\dfrac{(602.9)^2}{2\times9.8}[/tex]

[tex]h=1.8545\times10^{4}\ m[/tex]

We need to calculate the maximum height by second ball

Using conservation of energy

[tex]\dfrac{1}{2}mv^2=mgh[/tex]

[tex]h= \dfrac{v^2}{2g}[/tex]

Put the value into the formula

[tex]h=\dfrac{(1000)^2}{2\times9.8}[/tex]

[tex]h=5.1020\times10^{4}\ m[/tex]

(b). We need to calculate the total mechanical energy of the ball–Earth system at the maximum height for each ball

Using formula of energy

[tex]E=\dfrac{1}{2}mv^2[/tex]

[tex]E=\dfrac{1}{2}\times20\times1000^2[/tex]

[tex]E=1.0\times10^{7}\ J[/tex]

Hence, (a). The maximum height by first ball is [tex]1.8545\times10^{4}\ m[/tex]

The maximum height by second ball is [tex]5.1020\times10^{4}\ m[/tex]

(b). The total mechanical energy of the ball–Earth system at the maximum height for each ball is [tex]1.0\times10^{7}\ J[/tex]

A SMA wire in the un-stretched condition is then given an initial strain of εo (to preload the wire) at room temperature (RT). Its ends are then rigidly fixed. What force is developed in the wire?

Answers

Answer: tensional force

Explanation:

Tension force on a material occurs when two equal forces act on a material in an opposite direction away from the ends of the material.

Pre-tensing a wire material increases its load bearing capacity and reduces its flexure.

When light goes from one material into another material having a HIGHER index of refraction,

A) its speed decreases but its wavelength and frequency both increase.
B) its speed, wavelength, and frequency all decrease.
C) its speed increases, its wavelength decreases, and its frequency stays the same.
D) its speed decreases but its frequency and wavelength stay the same.
E) its speed and wavelength decrease, but its frequency stays the same.

Answers

Answer:

When light goes from one material into another material having a HIGHER index of refraction, its speed and wavelength decrease, but its frequency stays the same.

The correct option is E

Explanation:

Refraction is the bending of light ray as it crosses the boundary between the two media of different densities, thus causing a change in it's direction.

When light goes from one material of lower refractive to another material of higher refractive index, the speed of light reduces, because from law of refraction

aNg= (speed of light in air)/(speed of light in glass)

Snell's Law

So generally,

n1/n2 = v2/v1

Let n1 be incident index

Let n2 be refracted index

v2 is refracted speed

v1 is incident speed

Since given that, n1<n2

Then, the right side of the equation will always be less than 1 i.e n1/n2

Then, v2=v1• ( n1/n2)

Since n1/n2 is less that one this show that the speed v2 will reduce.

Since we know that the speed decrease,

We also know that speed, wavelength and speed is related by

v=fλ

Since, the speed is directly proportional to wavelength this shows that as the speed reduces the wavelength also reduces where frequency is the constant of proportionality

v∝λ. .

then f is constant of proportional

v=fλ

So as speed reduces, the wavelength reduces.

frequency of a light wave does not depend on the medium, while wavelength and speed do.

its speed and wavelength decrease, but its frequency stays the same.

Then the answer is E

Before entering a mass spectrometer, ions pass through a velocity selector consisting of parallel plates separated by 1.6 mm and having a potential difference of 148 V. The magnetic field between the plates is 0.42 T. The magnetic field in the mass spectrometer is 1.2 T.

1)(a) Find the speed of the ions entering the mass spectrometer.

m/s
2)(b) Find the difference in the diameters of the orbits of singly ionized 238U and 235U. (The mass of a 235U ion is 3.903 x 10-25 kg.)

mm

Answers

Answer:

1)   v = 2.20 10⁵ m / s , 2)  r = 4.86 10⁻³ m,    r = 4.92 10⁻³ m

Explanation:

1) A speed selector is a section where the magnetic and electrical forces have opposite directions, so

           [tex]F_{m} = F_{e}[/tex]

           q v B = q E

           v = E / B

           V = E s

           E = V / s

            v = V / s B

            v = 148 / (0.0016 0.42)

            v = 2.20 10⁵ m / s

2) when the isotopes enter the spectrometer, we can use Newton's second law

             F = m a

Acceleration is centripetal

             a = v² / r

             q v B = m v² / r

              r = m v / qB

The mass of uranium 235 is

           

           m = 3.903 10⁻²⁵ kg

The radius of this isotope is

             r = 3,903 10⁻²⁵ 2.20 10⁵ / (92  1.6 10⁻¹⁹  1.2)

             r = 4.86 10⁻³ m

The mass of the uranium isotope 238 is

              m = 238 a = 238 1.66 10-27 = 395.08 10-27 kg

The radius is

             r = 395.08 10⁻²⁷ 2.20 10⁵ / (92 1.6 10⁻¹⁹  1.2)

             r = 4.92 10⁻³ m

Final answer:

The speed of the ions entering the mass spectrometer is 352.38 m/s. The difference in the diameters of the orbits of the 238U and 235U ions can be calculated using the formula for the radius of a charged particle's orbit in a magnetic field.

Explanation:

To find the speed of the ions entering the mass spectrometer, we can use the equation for the force on a charged particle in a magnetic field: F = qvB, where F is the force, q is the charge, v is the velocity, and B is the magnetic field. The force is equal to the electric force, qE, so we can set these two equations equal to each other and solve for v: qvB = qE. Since q is the charge of the ion and E is the electric field strength, we can rearrange this equation to solve for v, giving us v = E/B.

Plugging in the values given in the question, we find that the speed of the ions entering the mass spectrometer is 148 V / 0.42 T = 352.38 m/s.

To find the difference in the diameters of the orbits of the 238U and 235U ions, we can use the formula for the radius of a charged particle's orbit in a magnetic field: r = mv / (qB), where m is the mass of the ion, v is its velocity, q is its charge, and B is the magnetic field. Since the ions are singly ionized, their charges are +e, where e is the charge of an electron. Plugging in the values given in the question, we can calculate the radius of the orbits of the 238U and 235U ions, and then subtract these values to find the difference in their diameters.

Other Questions
The Gilbert Instrument Corporation is considering replacing the wood steamer it currently uses to shape guitar sides. The steamer has 6 years of remaining life. If kept, the steamer will have depreciation expenses of $650 for 5 years and $325 for the sixth year. Its current book value is $3,575, and it can be sold on an Internet auction site for $4,150 at this time. If the old steamer is not replaced, it can be sold for $800 at the end of its useful life.Gilbert is considering purchasing the Side Steamer 3000, a higher-end steamer, which costs $13,000, and has an estimated useful life of 6 years with an estimated salvage value of $1,300. This steamer falls into the MACRS 5-years class, so the applicable depreciation rates are 20.00%, 32.00%, 19.20%, 11.52%, 11.52%, and 5.76%. The new steamer is faster and would allow for an output expansion, so sales would rise by $2,000 per year; even so, the new machine's much greater efficiency would reduce operating expenses by $1,600 per year. To support the greater sales, the new machine would require that inventories increase by $2,900, but accounts payable would simultaneously increase by $700. Gilbert's marginal federal-plus-state tax rate is 40%, and its WACC is 13%.Required:A) Should it replace the old steamer?B) What is the NPV of the project? (Round your answer to the nearest dollar.) Only a small amount of the energy used in an incandescent light bulb (regular bulbs commonly used in households) is actually converted into light. What happens to the rest of the energy Using the graph, complete the table that follows by indicating whether each statement is true or false. Statement True False a. Curve MM is more elastic between points A and C than curve NN is between points A and D.b. Between points A and B, curve LL is unit elastic. c. Between points A and D, curve NN is inelastic. Convert .4076grams into molesElement is copper Determine if the given side lengths could be used to form a unique triangle, many different triangles, or notriangles12 ft 7ft. 14 ftA unique triangleB many different trianglesC no triangles Hey guys, I could really use your help. Lots of points and brainly for a good answer.I just need to determine if these arguments are valid or invalid reasoning.Valid or Invalid? Women are the main breadwinners in two-thirds of families across the country.Valid or Invalid? Employers pay different workers different salaries based on skill level.Valid or Invalid? Paying people different salaries for the same work is discrimination.Valid or Invalid? Pay discrimination hurts middle class families.Valid or Invalid? Women are ready to fight back against pay discrimination.It would also be really helpful if you could explain why, im a bit confused as to the definition of invalid reasoning.Thanks! Explaining How to Compare Water Levels Ericka decided to compare her observation to the average annual trend, which shows the water rising 1.8 mm/year. Remember, she used 6.2 years as her time period. Explain how she would calculate the difference between how much water levels rose on average and how much the water level fell in the part of the river she observed. A compound containing only C, H, and O, was extracted from the bark of the sassafras tree. The combustion of 81.7 mg produced 222 mg of CO2 and 45.4 mg of H2O. The molar mass of the compound was 162 g/mol. Determine its empirical and molecular formulas. A 2.0 ???????? capacitor and a4.0 ???????? capacitor are connected in parallel across a 300 V potential difference. Calculate the total energy stored in the capacitor? For each sequence, find the first 4 terms and the 10th term.a.) n + 5b.) 2n 1 Three hours after eating at an airport fast-food restaurant, Karen got extremely nauseous while in flight. The next time she was in the airport and walked by that restaurant, she felt a wave of nausea. How can this be best explained? the conditioned stimulus Foster Designs sells different types of clothing for men and women. To ensure the retail store locations contain the appropriate assortment of clothing for the typical customer living in the area, the firm should use ______ segmentation. A small pizza has a diameter of 10 inches. A slice had a central angle of /3 radians. What is the area of the slice? How did US leaders think people would respond to a military draft during World War I? A ______ is a voluntary meeting arranged by a juvenile probation officer with the victim, the juvenile, and typically the juveniles parents or guardian in an attempt to negotiate a settlement without taking further official action Write a three- to five-sentence objective summary of Antigone, part 2, Section A, by Sophocles from Lesson 7. According to the American Psychological Association, when a graduate student submits his or her thesis or dissertation for publication jointly with the major professor, the first author should be:______. a. the student or the one who developed the idea for the study.b. the major professor whoever submits the study for publication. QUESTION 1: Using the experimental data, calculate the standard reduction potential for each metal, and organise them into a standard reduction table. Assume E for B is 0V.QUESTION 2: Deduce which two metals would produce the highest cell potential in a galvanic cell. Give reasons for your conclusion. Often a successful attack on an information system is due to poor system design or implementation. Once such a vulnerability is discovered, software developers quickly create and issue which of the following, in order to eliminate the problema. patchb. botc.logic bombd.Trojan horse Lenny works for Mechanical Engineers, P.A. While working on a Mechanical Engineers project, Lenny is injured. Under state workers compensation laws, Lenny will be compensated only if his injury was?a. ?accidental.b. ?intentional.c. ?material.d. ?incidental.