Answer:
F = 431671.31 [N]
Explanation:
This problem can be solved using the work and energy theorem, which tells us that the initial mechanical energy (potential energy + kinetic energy) plus the sum of the work from the initial position to the end will be equal to the final mechanical energy.
[tex]E_{M1}+W_{1-2}=E_{M2}\\0.5*m*v_{1}^{2}+W_{1-2}=0.5*m*v_{2}^{2}[/tex]
As the train stops at the end, the speed at Point 2 is equal to zero,so we can determine the work, we first convert the speed from [km/h] to meters per second.
[tex]250[\frac{km}{h}]*1[\frac{h}{3600s} ]*1000[\frac{m}{1km} ]\\= 69.44[\frac{m}{s} ][/tex]
[tex]0.5*(8.63*10^{5})*(69.44)^{2}+W_{1-2}= 0.5*(8.63*10^{5})*(0)^{2}\\W_{1-2}=-2080.66*10^6[J][/tex]
The negative sign means that the work is done in the opposite direction to the movement.
Knowing the work we can calculate the force, since an initial input data is the distance
W = F * d
F = W / d
F = (2080.66*10^6) / 4820
F = 431671.31 [N]
_____ All elements in this series are radioactive?
Answer:
Actinide series : All the elements in the actinides series are radiactive
Explanation:
The question is to fill in the blank which series of elements in the periodic table are radiactive.
The answer is the actnide series.
The actinide series is the elements in the same row as actinide since the same actnide (atomic number 89) to the lawrencium (atomic number 103).
Among other elements, this series include thorium, uranium and plutonium which are very known as radiactive elements, since they are used in nuclear reactors, which use nuclear fission reactions.
The reason for the radioactivity of these elements is the massive unstable nucleus.
A heavy nucleus means a large amount of positive charge (protons) concentrated in a tiny region (the nucleus of the atom).
The electrostatic repulsion among those so many protons is not balanced by the strong nuclear force (from the neutrons) resulting in the unstability (radioactivity) of the nucleus.
In a radioactive decay series, not all elements are radioactive. The series includes most of the naturally radioactive elements, but each series concludes with a stable, non-radioactive end-product, typically a stable isotope of lead.
Explanation:The question you've asked relates to Radioactive Decay Series. Naturally occurring radioactive isotopes of the heaviest elements fall into decay series. These series include most of the naturally radioactive elements of the periodic table such as the uranium series, the actinide series, and the thorium series. However, not all elements in these series are radioactive; each chain ultimately concludes with a stable end-product. For example, for all three mentioned series, the end-product is a stable isotope of lead. The concept of a decay series results from heavy nuclei decaying to a lighter one, with the lighter, daughter nucleus becoming the parent nucleus for the next decay.
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The answer and how to do it?? Thanks
The acceleration of the block is 4 m/s².
To find the acceleration of the 1kg block in the given diagram, we need to calculate the total force acting on the block and then divide it by the mass of the block.
Since there are three forces acting on the block, we can find the resultant force by adding these forces together.
In this case, the forces are 5N, 4N, and 5N in different directions.
Combining these forces, we get a net force of 4N in the horizontal direction.
Since the mass of the block is 1kg, the acceleration can be calculated using Newton's second law of motion: F = ma.
Therefore, the acceleration of the block is 4 m/s².
which land class has the least restrictions and is best for cultivation
Answer:
land scaping
Explanation:it makes your yard look lit imfao
Answer:
class #3
Explanation:
The soils are deep, well-drained, easily worked, hold water well and are either fairly well supplied with plant nutrients or highly responsive to the application of fertilizers.
Gabby puts a 5.8 kg weight on a spring and it stretches 1.4 m. What is the spring constant of the spring? (Remember kg is not a force it is a mass) (F = Kx)
Answer:
40.6 N/m
Explanation:
From Hooke's law we relate the extension of a spring and the applied force by the formula F=kx where F is the applied force, k is spring constant and x is extension of spring.
Making k the subject of the formula then we have
[tex]k=\frac {F}{x}[/tex]
We also know that F=gm where g is acceleration due to gravity which we take as 9.81 m/s2 while m is the mass. Substituting F with gm into the formula we get that
[tex]k=\frac {gm}{x}[/tex]
Substituting m for 5.8 kg and x for 1.4 m we get the spring conatant as
[tex]k=\frac {9.81\times 5.8}{1.4}=40.641428571428\ N/m\approx 40.6\ N/m[/tex]
Therefore, the spring constant is approximately 40.6 N/m
The diagram shows the electric field due to point charge Q. Which statements are correct? Check all that apply.
Answer:
The correct statements are:
A. The electric field is nonuniform.D. Charge Q is positive.E. If charge A moves toward charge Q, it must be a negative chargeExplanation:
The answer choices are:
A. The electric field is nonuniform.B. The electric field is uniform.C. Charge Q is negative.D. Charge Q is positive.E. If charge A moves toward charge Q, it must be a negative charge.F. If charge A moves toward charge Q, it must be a positive charge.SolutionThe electric field is the electrostatic force per unit of charge,
[tex]\vec E=\dfrac{\vec F}{Q}[/tex]
around around a charge, where another charge would experience the electrostatic force.
The electric field lines are shown in a diagram with arrows ditributed radially away from a positive charge and radially toward a negative charge.
Since the arrows are away from Q, Q is a positive charge: statement D.
Since the size of the arrows decreases as you move away from Q the stregth of the field is not uniform: statement A.
Since the charge Q is positive, a negative charge would be attracted toward it: statement E.
You serve a volleyball with mass of 2.1kg. The call leaves your hand at 30m/s. The ball has Energy calculate it
Answer: 945 joules
Explanation:
Given that:
mass of volleyball = 2.1kg.
Speed at moving volleyball = 30m/s. Energy possessed by volleyball = ?
Recall that the energy possessed by a moving object is known as kinetic energy. Thus, the moving volleyball has kinetic energy.
So, apply the formula for kinetic energy
K.E = 1/2 x mass x speed^2
K.E = 1/2 x 2.1kg x (30m/s)^2
K.E = 0.5 x 2.1kg x 900
K.E = 945 Joules
Thus, the volleyball has kinetic energy of the 945 joules
A driver starts is parked car and within 5 seconds reaches a speed of 60km/h, as he travels east. What his acceleration?
The acceleration of the car is 3.3 m/s²
Explanation:
Given-
Speed of the car, (we can represent as s) = 60 km/hr = 60 × [tex]\frac{5}{18}[/tex] = 16.67 m/s
Time,(we can represent as t) = 5 s
Acceleration, (we can represent as a) = ?
We know,
a = [tex]\frac{s}{t}[/tex]
a = [tex]\frac{16.67}{5}[/tex]
a = 3.334 m/s²
The acceleration of the car is 3.3 m/s²
The field lines around one end of a bar magnet are shown
below
Based on the diagram, what can you conclude about the
pole of the magnet?
A.)It is a south pole because the field lines spread out from
this end
B.)It is a north pole becaust the field lines spread out from
this end
C.)It is a south pole because the field lines enter the
magnet at this end.
D.)It is a north pole because the field lines enter the
magnet at this end.
Answer:
Explanation:
Field lines are lines of forces around a bar magnet. The show the direction of force field in a magnet.
Usually, around a bar magnet, the field lines originates and spreads out from the north pole.
Then they converge and enter through the south pole.
Therefore, we can make our choice by inspecting the given diagram. If the lines enters through the pole, it is the south pole.
Where they originate or leave is the north pole.
In a magnet, the lines (forces) always enter through the south pole and leave through the north pole.
I hope that helps ya'll.
- sincerelynini
PLEASE MARK BRAINLIEST!in which medium does sound travel the fastest
Answer:
Solids
Explanation:
Aluminum
Explanation:
Objects that are not moving have NO _____. A. mass (only) B. mass and momentum (only) C. velocity and momentum (only) D. mass, velocity, and momentum
Answer:
Objects that are not moving have NO velocity and momentum (only)
Explanation:
This best explains the potential energy of an object, when an object is at rest. it is said to have possessed a potential energy but without velocity and momentum i.e energy at rest
which best describes oil and water
The correct answer is option C. The hydrogen bonding between the water molecules is much stronger than the dipole induced dipole forces between the water and nonpolar oil molecules.
Option C is correct because water’s hydrogen bonding is much stronger than the dipole induced dipole interactions between water and nonpolar oil molecules.
Why other options are incorrect:
Option A is incorrect because the lack of ionization is not the reason; oil is nonpolar and does not interact well with polar water.Option B is incorrect because dispersion forces in oil are not significantly stronger than the forces between water and oil; the primary issue is the mismatch in polarity.Option D is incorrect because density is not the factor; the issue is the difference in polarity between water and oil.The complete question is:
Which of the following best explains why oil and water don't mix?
a) Oil molecules can't dissociate into ions on dissolution into water.
b) The dispersion forces between the oil molecules are much stronger than the dipole induced dipole forces between the water and nonpolar oil molecules.
c) The hydrogen bonding between the water molecules is much stronger than the dipole induced dipole forces between the water and nonpolar oil molecules.
d) Water is too dense to allow the oil to dissolve in it of the water is too oil is.
what is the best book for physics practicals??(pdf)
Answer:
I would strongly recommend Exploring Quantum Physics through Hands-on Projects for physics practicals.
Explanation:
Though it is not about books, but it is solely on you how you want to get knowledge. If you are truly passionate about learning physics in a practical way "Exploring Quantum Physics through Hands-on Projects" will be the best one out there.Besides "Laboratory Projects in Physics, a Manual of Practical Experiments for Beginners" is also a promising one.There are detailed chapters on important topics like light as a wave and particles, atoms and radioactivity, Schrödinger, etc.If you wisely follow these books, you will surely get all your doubts cleared and learn new mechanisms easily.The best book for physics practicals, particularly for university-level students, is often considered to be 'Principles and Practice of Physics' by Eric Mazur due to its clear examples and structured sequence. OpenStax's 'University Physics I' is an excellent alternative with open-source availability. A balance of textbooks, resources, and instructor guidance can provide a robust physics learning experience.
When searching for the best book for physics practicals, the University Physics I by Eric Mazur, entitled Principles and Practice of Physics, comes highly recommended. This book is known for its clear explanations, terminology consistency with other resources, and its sequence of content presentation. It is packed with worked-out examples and offers self-quiz conceptual questions that are crucial for understanding practical aspects of physics.
Alternatively, students looking for online and open-source textbooks can turn to resources like University Physics I at OpenStax, which offers an abundance of exercises and a more traditional presentation style. For computational physics enthusiasts, texts like A Practical Introduction to Computational Physics and Scientific Computing could be explored.
Ultimately, these books along with different ways to digest physics concepts, such as discussions with instructors and accessing resources in the Physics library, can cater to the diverse needs of physics students. It's important to consider one's own learning style and curriculum requirements when choosing the right practical physics text.
explain why magnets have poles
Answer: The force of a magnetic field on a particle with spin causes the particle to rotate it's spin to align with the magnetic field. ... Taking these two ideas together, then, the Earth's magnetic field will cause the magnet to align north to south. That's why people named them the north and south poles.
Explanation: Hope i could help please mark as brainliest!
The centre of gravity of a body may not be necessary on the body. Justify
Answer:
Your center of gravity
Explanation:
like everyone has there own center of gravity by there weight because that is going to see hows your balance, if I'm right
The center of gravity is the point where the total weight of a body is concentrated, but it may not always be on the body itself. This can be observed in situations like an unbalanced car wheel or a human standing, where the center of mass does not align with the geometric center.
The center of gravity of a body is the point where the total weight of the body is assumed to be concentrated. However, it does not necessarily need to be located on the body itself. This concept is particularly important in understanding the balance and stability of objects. For instance, a car wheel that has not been balanced properly has a center of mass that does not coincide with its geometrical center. Moreover, in a situation like a human standing, by shifting their weight, they can cause the center of mass to hang in space - a point that might not correspond with any actual material part of the body.
Three-dimensional bodies demonstrate this when they are in motion, such as when a stick is thrown in the air and seems to rotate around a single point. This occurs because the center of mass carries the whole mass of the body, contributing to the observed motion. Even large structures, such as buildings or cruise ships, despite their size, are located in a uniform gravitational field on Earth, which means the acceleration due to gravity is constant and the center of gravity and center of mass coincide.
Objects with odd shapes or missing parts can also have a center of gravity outside their physical form. Imagine a horseshoe where the center of gravity would be somewhere near the bottom, even though there's no material there.
Consider a hollow ring, the mass is concentrated around the rim, not in the center. As a result, the center of gravity would lie somewhere within the ring, not necessarily on the actual body.
Light travels through a substance at 1.97 x 10^8 m/s. What is the index of the liquid? What type of liquid is it?
The refractive index of the liquid is 1.52. The substance is a crown glass.
Explanation:
Given:
Velocity of light through the substance, v = 1.97 X 10⁸ m/s
Refractive index of the liquid, μ = ?
We know,
μ = [tex]\frac{c}{v}[/tex]
where, c = velocity of light in air
v = velocity of light in the substance
speed of light in air is 3 X 10⁸m/s
[tex]= \frac{3 X 10^8}{1.97 X 10^8} \\\\= 1.52\\[/tex]
Therefore, refractive index of the liquid is 1.52. The substance is a crown glass.
n = 1.52
Index of the liquid = 1.52
The type of the liquid is Crown glass.
Explanation:
In finding the index of refraction, we use this formula
n = c/v
where n is the index of refraction
c is velocity of light in vacuum which is constant and is equivalent to [tex]3 \times 10^{8} \mathrm{m} / \mathrm{s}[/tex]
v is the velocity of light in a particular medium
Here we use [tex]1.97 \times 10^{8} \mathrm{m} / \mathrm{s}[/tex]
Using the formula,
n = c/v
n = [tex]3 \times 10^{8} / 1.97 \times 10^{8}[/tex]
n = 1.52284264
n = 1.52
Thus, the index of the liquid is 1.52
Girl who’s mass is 52kg, experienced a net force of 1800N at bottom of a roller coster loop during her school physics field to the local amusement park, determine Sophia’s acceleration at location.
Answer:
34.62m/s^2
Explanation:
Force = mass x acceleration
Given
Force = 1800N
Mass = 52kg
Therefore
1800 = 52 x a
Divide both sides by 52
1800/52 = 52/52 x a
34.62 = a
a = 34.62m/s^2
F= 90 N
D= 5 m
W= ?
A. 18 j
B. 0.05 j
C. 450 j
D. 550 j
Answer:
c I hope this helpssssss :)
A cetain car weighs 25,000 N. Calculate the mass of the car.
245.000 kg
25,000 kg
9.81 m/s2
2,500 kg
Answer:2500kg
Explanation:
Weight of car(w)=25000N
Acceleration due to gravity approximately(g) 10m/s^2
Mass=w/g
Mass=25000/10
Mass=2500kg
A 37.9 A current flows in a long, straight wire. Find the strength of the resulting magnetic field at a distance of 45.5 cm from
the wire.
Answer:
[tex]1.67\cdot 10^{-5} T[/tex]
Explanation:
The magnitude of the magnetic field produced by a current-carrying wire is given by the equation:
[tex]B=\frac{\mu_0 I}{2\pi r}[/tex]
where:
[tex]\mu_0=4\pi \cdot 10^{-7} H/m[/tex] is the vaacuum permeability
I is the current in the wire
r is the distance from the wire
The direction of the magnetic field lines is tangential to concentric circles around the wire.
In this problem, we have:
[tex]I=37.9 A[/tex] is the current in the wire
[tex]r=45.5 cm = 0.455 m[/tex] is the distance from the wire
Solving for B, we find the magnitude of the magnetic field:
[tex]B=\frac{\mu_0 I}{2\pi r}=\frac{(4\pi \cdot 10^{-7})(37.9)}{2\pi (0.455)}=1.67\cdot 10^{-5} T[/tex]
A 10 N force is applied to a hockey puck over a period of 0.1 s. What is the change in momentum of the hockey puck?
Final answer:
The change in momentum of the hockey puck is 1 kg·m/s.
Explanation:
The change in momentum of an object can be calculated using the equation: change in momentum = force x time.
In this case, the force applied to the hockey puck is 10 N and the time period over which the force is applied is 0.1 s. Therefore, the change in momentum of the hockey puck is 10 N x 0.1 s = 1 kg·m/s.
a heavy object falls with the acceleration as a light object during free fall. Why?
A heavy object falls with the acceleration as a light object during free fall because of acceleration due to gravity.
Explanation:
A motion can be termed as free fall when the object is completely under the influence of gravity. So in this case, no other force will be acting on the object other than the gravitational force. As the gravity influences the object in free fall, the acceleration attained by any object in free fall is same. And this acceleration is termed as acceleration due to gravity. Since, the gravity gives the acceleration to every object experiencing free fall, then the acceleration should be constant. Thus, a heavy object and a light object will have same acceleration during free fall.
5. A 5.5 x10-6 C charge is located 0.28 m from a -3.5 x 10-6 C charge.
a) What is the magnitude of the force that the positive charge exerts on the negative charge?
b) If the negative charge was doubled, how would the force change?
(a) The magnitude of force that the positive charge exerts on the negative charge is - 2.209 N.
(b) If the negative charge is doubled, then the force will also get doubled.
The new force will be F = -4.418 N.
Explanation:
The force acting between two charged particles separated by a distance is termed as Coloumb's force or electrostatic force. It can be termed as electrostatic force of attraction if the the force acting between the charges are oppositely charged. And it can be termed as electrostatic force of repulsion if the charges are similar or like charges.
In the present case, there is a positive and negative charge, so electrostatic force of attraction will be acting between them. As per Coloumb's law, the electrostatic force of attraction is directly proportional to the product of charges and inversely proportional to the square of distance of separation.
[tex]F = \frac{kQq}{d^{2} }[/tex]
Here, k is the constant of proportionality which is equal to 9 ×[tex]10^{9}[/tex] and Q, q are the two charges, d is the distance of separation.
So here Q = 5.5 ×[tex]10^{-6} C[/tex] and q = - 3.5 ×[tex]10^{-6} C[/tex] and d = 0.28 m
Then, [tex]F=-\frac{9*10^{9}*5.5*10^{-6} * 3.5 * 10^{-6} }{(0.28)^{2} } = 2209.82*10^{-3}[/tex]
So the magnitude of force that the positive charge exerts on the negative charge is - 2.209 N.
(b) If the negative charge is doubled, then the force will also get doubled.
The new force will be F = -4.418 N.
The question requires the calculation of the electric force between two point charges using Coulomb's law and understanding how changes in the magnitude of one charge affect the force.
Explanation:The question involves understanding and applying Coulomb's law, which describes the electric force between two point charges.
a) Magnitude of the Force
To find the magnitude of the force that one charge exerts on another, we use the formula given by Coulomb's law:
[tex]F = k * |q1 * q2| / r^2[/tex]
Where:
F is the magnitude of the force between charges,k is the Coulomb's constant [tex](8.9875 x 10^9 N m^2/C^2),[/tex]q1 and q2 are the charges [tex](5.5 x 10^-6 C and -3.5 x 10^-6 C respectively),[/tex]r is the separation between the charges (0.28 m).Plugging in the values, we calculate F.
b) Effect of Doubling the Negative Charge
If the negative charge was doubled, the new charge would become [tex]-7.0 x 10^-6 C.[/tex] Since the force is directly proportional to the product of the two charges, doubling one of the charges would double the force as well.
Which statement correctly describes the formation of an electric current? A resistance causes electric charges to move from lower to higher potential. A voltage causes electric charges to move from lower to higher potential. A resistance causes electric charges to move from higher to lower potential. A voltage causes electric charges to move from higher to lower potentia
Answer:
.
Explanation:
Answer:
d. A voltage causes electric charges to move from higher to lower potential.
Explanation:
Desiree has a scientific question that she wants to investigate. She has developed a hypothesis and method for her experiment. Which step of scientific inquiry should Desiree take next?
Desiree should present her findings to her teacher and classmates.
Desiree should collect data, which may support or refute her hypothesis.
Desiree should provide an explanation for her results.
Answer:
Desiree should collect data, which may support or refute her hypothesis.
Explanation:
The next step Desiree must take is to collect data which might likely support or refute her hypothesis.
This is usually done by carrying out experiments or field studies.
The scientific method provides the steps through which knowledge of science is investigated. It usually starts with observation. After an observation is made, a scientific question is asked. This leads to the development of hypothesis. Then, experiments are carried out and data collect to either bolster the claim or refute it. Interpretation follows and conclusion is draw.Desiree should proceed to the step of collecting data, which may support or refute her hypothesis. Therefore option B is correct.
Collecting data is a crucial stage in the scientific inquiry process. It involves conducting experiments or observations to gather information that can either confirm or contradict the hypothesis she has formulated.
By systematically collecting and analyzing data, Desiree can draw conclusions based on empirical evidence. This step forms the backbone of scientific investigation as it provides the tangible information required to validate or revise her hypothesis.
Once she has sufficient data, Desiree can move on to analyzing her results and drawing meaningful conclusions, paving the way for the interpretation and potential communication of her findings.
Therefore option B is correct.
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In the following diagram, the voltage is 1.5 volts and the resistance is 0.35 ohms. Use Ohm's Law to determine the current in the circuit.
Answer:
I = 4.28 [amp]
Explanation:
To solve this type of problems we must have knowledge of the law of ohm, which tells us that the voltage is equal to the product of resistance by current.
Initial data:
v = 1.5 [volt]
R = 0.35 [ohms]
v = I * R
therefore:
I = 1.5 / 0.35
I = 4.28 [amp]
Final answer:
Using Ohm's Law, the current in the circuit with a voltage of 1.5 volts and a resistance of 0.35 ohms is calculated to be approximately 4.286 amperes.
Explanation:
To determine the current in the circuit, we can use Ohm's Law, which is stated as I = V/R, where I is the current in amperes, V is the voltage in volts, and R is the resistance in ohms. Given that the voltage (V) is 1.5 volts and the resistance (R) is 0.35 ohms, we can substitute these values into the equation to calculate the current.
Thus, the current (I) can be calculated as follows:
I = 1.5V / 0.35Ω = 4.286 amperes (approx).
This means that the current flowing through the circuit is approximately 4.286 amperes.
A 82-kg skydiver has a speed of 40 m/s at an altitude of 490 m above the ground. Calculate the total mechanical energy of the skydiver.
Answer:
[tex]ME=459,364J[/tex]
Explanation:
Mechanical Energy=Potential Energy+ kinetic Energy
[tex]m=82kg,g=9.8N/kg,h=490m,v=40m/s[/tex]
To calculate Kinetic Energy:-
[tex]KE=\frac{1}[2}mv^2\\=\frac{1}{2}\times82kg \times(40m/s)^2\\=65600J[/tex]
To calculate Potential Energy:-
[tex]PE=mgh\\=82kg \times9.8N/kg \times490\\=393764[/tex]
therefore,
[tex]ME=KE+PE\\=65600+393764\\=459364J[/tex]
The skydiver's total mechanical energy is 459365J
Final answer:
The total mechanical energy of an 82-kg skydiver moving at 40 m/s at an altitude of 490 m above the ground is calculated as 458876 Joules, which includes both kinetic and potential energy.
Explanation:
Calculating Total Mechanical Energy of a Skydiver
To calculate the total mechanical energy of a 82-kg skydiver moving at a speed of 40 m/s at an altitude of 490 m above the ground, we need to consider both kinetic and potential energy.
Kinetic energy (KE) is given by the formula: KE = 0.5 Times m times v2
Gravitational potential energy (PE) is given by the formula: PE = m times g Times h
Where:
m is the mass of the skydiver (82 kg)
v is the velocity (40 m/s)
g is the acceleration due to gravity (9.8 m/s2)
h is the height above the ground (490 m)
Now we perform the calculations:
KE = 0.5 imes 82 kg times (40 m/s)2 = 0.5 times 82 times 1600 = 65600 J
PE = 82 kg times 9.8 m/s2 times 490 m = 82 times 9.8 times 490 = 393276 J
The total mechanical energy (Etotal) is the sum of kinetic and potential energy:
Etotal = KE + PE = 65600 J + 393276 J = 458876 J
Therefore, the total mechanical energy of the skydiver is 458876 Joules.
A 0.14 -kg baseball is moving at 41 m/s. A 0.058-kg tennis ball is moving at 67 m/s. Which of the two balls has higher kinetic energy?
Answer:The answer is tennis ball
Explanation:
i know this cause I'm good at math and why wouldn't you trust a random guy off the internet.
What contributes the most to food waste in America
According to the USDA, 40% of our food worth $161 billion is not even harvested, lost in processing, thrown away in restaurants and homes or ended up rotting in America’s landfills. It is also reported that 50% of the produce is never consumed.
Disparities in food distribution and availability imply that numerous communities and neighborhoods have very constrained access to fresh affordable food. Also, a significant number of those with a bounty of food choose to toss it rather than donate it.
Another type of food waste comes from produce discarded by millions of backyard cultivators due to their gardens producing far more fruits and vegetables than they might use, preserve or give to friends and neighbours.
a 60 kg child sits on on the outer edge a playground merry-go-around with radius of 4 meters that spins around at 1 revolution every 5 seconds, mercilessly bringing the child ever closer to nausea. What is the child's angular momentum? ( Remember to include the units.) What is the angular momentum of another child with the same mass who is sitting half way out from the center?
Answer:
a) [tex]1209.6 kg m^2/s[/tex]
b) [tex]302.4 kg m^2/s[/tex]
Explanation:
a)
The angular momentum of an object in circular motion is given by the formula
[tex]L=m\omega r^2[/tex]
where
m is its mass
[tex]\omega[/tex] is its angular velocity
r is the distance of the object from the axis of rotation
For the child in this problem, we have:
m = 60 kg is his mass
r = 4 m is the radius of the merry-go-around
Here the child completes 1 revolution every 5 seconds; so his frequency is
[tex]f=\frac{1}{5}=0.2 Hz[/tex]
And so his angular speed is
[tex]\omega=2\pi f=2\pi 0.2=1.26rad/s[/tex]
Therefore, the angular momentum is
[tex]L=(60)(1.26)(4)^2=1209.6 kg m^2/s[/tex]
b)
For a child sitting halfway of the merry-go-around, his distance from the axis of rotation is
[tex]r=\frac{4 m}{2}=2 m[/tex]
The mass of the child is the same as before,
m = 60 kg
And the angular speed is the same as well: in fact, the merry go around is a rigid body, so all its points cover the same angle in the same time; so, they all have the same angular speed. Therefore,
[tex]\omega=1.26 rad/s[/tex]
Therefore, the angular momentum here is:
[tex]L=m\omega r^2 = (60)(1.26)(2)^2=302.4 kg m^2/s[/tex]
a current-carrying wire has the maximum magnetic force in it when it is placed in a constant magnetic field when
Answer:
Maximum magnetic force on current carrying wire when wire is placed at 90 degree with magnetic field
Explanation:
As we know that the magnetic force on current carrying conductor is given as
[tex]\vec F = i(\vec L \times \vec B)[/tex]
here we have
[tex]F = i L Bsin\theta[/tex]
here we know that
[tex]\theta [/tex] = angle between length vector and magnetic field vector
so if we would like to have maximum magnetic force on the current carrying wire then
[tex]\theta = 90 [/tex]
so we have
[tex]F_{mex} = iLB[/tex]