Final answer:
The centripetal force on the sensor is 2544.06 N.
Explanation:
To calculate the centripetal force of on the sensor attached at the end of the wind turbine blade, we can use the formula:
F = m * r * ω²
Where F is the centripetal force, m is the mass of the sensor, r is the radius of the wind turbine blade, and ω is the angular velocity.
Substituting the given values, we have: F = 4.5 kg * 90.0 m * (2π rad/s).
After calculating, we get the centripetal force on the sensor to be 2544.06 N.
explain how friction affects the mechanical energy of a system
Friction decreases the kinetic energy which decreases the mechanical energy.
Explanation:When two object moves one over the other, the resistance that is faced by the object is called as the friction. Any force that restricts the motion of any moving or any object that is sliding is called as friction. A kinetic energy can be considered as a non conservative energy that reduced the mechanical energy of any moving objects.
A friction can be considered as a force that resits motion of an object. When there a movement of two objects one against the other, there will be a conversion of kinetic energy into heat energy. This conversion is caused by the friction. Thus, the kinetic energy reduces the mechanical energy and they will be converted into heat energy.
Friction is a force that opposes motion, transforming mechanical energy into other forms like heat, effectively reducing the system's mechanical energy.
Explanation:Friction is a force that opposes the movement or motion of an object. In a system, when there is movement, friction comes into play. Mechanical energy is the sum of kinetic and potential energy in a system. As friction acts against movement, it transforms the mechanical energy within the system into other forms of energy, such as heat energy, which reduces the system's mechanical energy. Let's consider a sliding block for example. As the block slides, the friction between the block and the surface generates heat, thus reducing the mechanical energy (kinetic energy) of the block.
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what is the force acting on the object?(g=10m/s^2)
Answer:w=mxg
2x10 =20 N
Explanation:force acting downwards is mg mass into gravitional feild
7. What causes waves to bend?
Answer:
Refraction
Explanation:
Refraction is the change in direction of waves that occurs when waves travel from one medium to another. Refraction is always accompanied by a wavelength and speed change. Diffraction is the bending of waves around obstacles and openings.
Waves bend or 'refract' when they move from one medium to another and change speed. This bending is impacted by the properties of the mediums and the angle of the incident wave. A common example is the apparent bending of a stick immersed in water, which we see as a result of light wave refraction.
Explanation:The bending of waves, whether light, sound, or oceanic, is primarily caused by a phenomenon known as refraction. Refraction occurs when a wave moves from one medium to another, causing a change in speed and resulting in bending of the wave. A typical example of this is the apparent bending of a stick when it is partially immersed in water; what we're seeing is the refraction, or bending, of light waves as they move from water to air.
The extent of bending, or refraction angle, depends on the nature and properties of the transmitting mediums and the incident wave angle. When waves cross the boundary between different mediums at an angle, one side of the wave changes speed before the other, causing the wave to bend towards the medium that slows it down.
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If the speed of an object were to triple, what would be the increase of kinetic energy?
KE↓2=_____KE↓1
1. 1/3
2. 1/9
3. 3
4. 9
Answer:
4. 9
Explanation:
For instance, if the speed of an object becomes double, its kinetic energy changes to four times the initial kinetic energy.Similarly, if the speed of the object triples the kinetic energy becomes nine times the initial kinetic energy.
Therefore the answer is 9.
A clear echo is heard within 0.2 seconds when a person shouts by sitting at the ridge of a hill. Calculate the velocity of sound in air. The distance between the person and the hill is 33.2 m
To calculate the velocity of sound in air using the given information, we'll use the formula:
Speed=(distance)/(Time).Therefore, the velocity of sound in air is 332m/s.
To calculate the velocity of sound in air using the given information, we'll use the formula:
Speed=(distance)/(Time)
Given:
Time taken for the echo(t) = 0.2 seconds
Distance between the person and the hill(d) = 33.2 meters
Firstly, recognize that the sound traveled twice the distance (to the hill and back) to create the echo.
So, the actual distance the sound traveled is 2×distance=2×33.2meters=66.4meters.
Next, use the formula for speed:
Speed=(distance)/(Time)
Speed=(66.4m)/(0.2s)
Speed=332m/s
Therefore, the velocity of sound in air is 332m/s.
Which of these is changed by the Milankovitch cycles?
A) the reflectivity of Earth
B) the amount of solar energy that reaches Earth
C) the length of a year on Earth
D) the duration of seasons on Earth
The amount of solar energy that reaches Earth is changed by Milankovitch cycles.
Explanation:
Milankovitch cycles occur due to slight changes in the orbit of the Earth around the Sun. These could be changes in its eccentricity or even tilt in the axis.These cycles caused due to small changes have different effects on how much solar energy reaches the Earth and the time at which maximum sunlight is received.These cycles are very important as the amount of solar energy or sunlight reaching the Earth also affects the climate on the Earth. The ice ages are examples of such changes in the climate. They are strongly connected to the changes in the orbit of the Earth.The Milankovitch cycles affect the amount of solar energy reaching Earth through changes in Earth's orbital shape and axial tilt over thousands of years. The correct option is B) the amount of solar energy that reaches Earth.
Explanation:The Milankovitch cycles affect the amount of solar energy that reaches Earth. These cycles consist of changes in Earth's orbit and axial tilt over thousands of years. Of the options provided, B) the amount of solar energy that reaches Earth is the aspect that is changed by the Milankovitch cycles. Specifically, eccentricity, which is one of these cycles, alters the shape of Earth's orbital path from more circular to more elliptical over approximately 100,000 years. This affects the proximity of Earth to the sun during various parts of the orbit, thereby influencing the solar radiation the planet receives.
What is the difference between kinetic and potential energy and how do they work?
To explain, I will use the equations for kinetic and potential energy:
[tex]PE = mgh\\KE = \frac{1}{2}mv^{2}[/tex]
Potential energyPotential energy is the potential an object has to move due to gravity. An object can only have potential energy if 1) gravity is present and 2) it is above the ground at height h. If gravity = 0 or height = 0, there is no potential energy. Example:
An object of 5 kg is sitting on a table 5 meters above the ground on earth (g = 9.8 m/s^2). What is the object's gravitational potential energy? (answer: 5*5*9.8 = 245 J)
(gravitational potential energy is potential energy)
Kinetic energyKinetic energy is the energy of an object has while in motion. An object can only have kinetic energy if the object has a non-zero velocity (it is moving and not stationary). An example:
An object of 5 kg is moving at 5 m/s. What is the object's kinetic energy? (answer: 5*5 = 25 J)
Kinetic and Potential EnergySometimes, an object can have both kinetic and potential energy. If an object is moving (kinetic energy) and is above the ground (potential), it will have both. To find the total (mechanical) energy, you can add the kinetic and potential energies together. An example:
An object of 5 kg is moving on a 5 meter table at 10 m/s. What is the objects mechanical (total) energy? (answer: KE = .5(5)(10^2) = 250 J; PE = (5)(9.8)(5) = 245 J; total: 245 + 250 = 495 J)
Which of the following is the most accurate description of the relationship between velocity
and acceleration?
A. Velocity and acceleration are the same thing.
B. Velocity is a type of acceleration.
C. Acceleration is a change in velocity.
D. Acceleration is positive and velocity is negative.
Answer:
(C) acceleration is a change in velocity.
Explanation :
Acceleration is the rate of change of velocity with time.
Acceleration is the rate at which velocity changes, making option C ('Acceleration is a change in velocity.') the most accurate description of the relationship between velocity and acceleration.
Explanation:The most accurate description of the relationship between velocity and acceleration is that acceleration is the rate at which velocity changes. Therefore, the correct answer to the question is 'C. Acceleration is a change in velocity.'
Acceleration is a vector quantity, which means it has both magnitude and direction. It can result from a change in speed, a change in direction, or both. Velocity is also a vector that describes the speed of an object in a given direction. When an object's velocity changes, it is accelerating, which can be a result of increasing speed, decreasing speed, or changing direction.
In summary, while velocity is the rate of change of position with time, acceleration is the rate of change of velocity with time.
A student measures the mass and gravitational force on one textbook. If you double the mass by using two textbooks, what would happen to the gravitational force?
the force would not change
the force would more than double
the force would less than double
the force would double
Answer:
the force would not change
Explanation:
the answer is the force would double. i just did the test and got it right!
A construction worker drags a box across the floor. If the frictional force between the floor and the box is 12.2 newtons, how much work does friction do as the box moves 11.5 meters?
The work done is 140.3 J
Explanation:
The work done is defined as the amount of force required or used to move an object over a particular distance. Hence, work done is the product of force in Newton and the distance in which the object moved in meters. Here, in the question, it is given that there is a frictional force acting on the box by the floor and the distance it moves. Hence, to get the answer to multiply frictional force and the distance. So, will get the work done as 140.3 J.Final answer:
The work done by the frictional force as the box moves 11.5 meters is -140.3 joules, indicating the force is opposing the box's motion.
Explanation:
To calculate the work done by friction as a box moves across a floor, we need to use the equation for work, which is work done (W) = force (f) × distance (d) × cos(θ), where θ is the angle between the force and the direction of motion. Since friction always acts opposite to the direction of motion, the angle θ here is 180 degrees, and cos(180°) is -1. Therefore, the work done by the frictional force is negative, indicating that it's in the opposite direction to the displacement of the box.
The frictional force between the box and the floor is given as 12.2 newtons, and the box moves 11.5 meters. Substituting the given values into the work equation gives:
W = f × d × cos(180°) = 12.2 N × 11.5 m × (-1) = -140.3 joules.
The negative sign indicates that the work done by the frictional force is in the opposite direction of the displacement, meaning it resists the motion of the box.
The amusement park ride shown above takes riders straight up a tall tower and then releases an apparatus holding seats. This apparatus free-falls back to Earth and is stopped safely right above the ground. Which of the following indicates the magnitude of the gravitational force exerted on a rider of mass m on the way up and on the way down?
The answer & explanation for this question is given in the attachment below.
The magnitude of the gravitational force exerted on a rider of mass m during both ascent and descent on an amusement park ride is defined as F = mg, with F being the gravitational force, m the mass of the rider, and g the acceleration due to gravity (~9.81 m/s²).
Explanation:The gravitational force exerted on a rider with a mass m during both ascent and descent in an amusement park ride is characterized by the same magnitude. This force is given by the expression F = mg, where F is the gravitational force, m is the mass of the rider, and g is the acceleration due to gravity, which is approximately 9.81 m/s² on Earth. Let's break this down:
On the way up: The gravitational force is acting downwards, against the motion of the rider. This force works to slow the upward motion of the rider.On the way down: The gravitational force is acting downwards, in the same direction as the motion of the rider. This force is what causes the rider to accelerate downwards, or free-fall, until the apparatus is safely stopped just above the ground.In both scenarios, note that the actual sensation the rider feels (the 'felt' force) might be different due to the combination of gravitational force and the inertia of the rider's body. This inertia entails a resistance to changes in motion and can lead to what we often describe as the 'thrill' of the ride.
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9. An 800 kg police boat slows down uniformly from 50 km/h [E] to 20 km/h (E) as it enters a
harbour. If the boat slows down over a 30 m distance, what is the force of friction on the boat?
(Hint: You will need to convert the velocities into m/s.)
Answer:
2,158N
Explanation:
According to the second newtons law of motion, Force(F) = mass(m) × acceleration (a)... 1
Given mass to be 800kg.
We need to get the acceleration of the body using one of the equations of motion.
v²= u²+2as ... (2)where;
v = final velocity = 50km/hr
u = initial velocity = 20km/hr
a is the acceleration
s is the distance covered by the boat = 30m
Converting 50km/hr and 20km/hr to m/s, this gives us
50km×1000m/1hr×3600s
= 50000/3600
= 13.9m/s
Similarly,
20km/hr = 20000m/3600s
= 5.6m/s
Substituting this values into the equation 2 to get acceleration, we have
13.9²= 5.6²+2a(30)
193.21 = 31.36+60a
60a = 193.21-31.36
60a = 161.85
a = 2.69m/s²
To get the force on the both we substitute the value of mass and acceleration in equation 1
F =ma
F = 800×2.69
F= 2,158N
Therefore the force of friction on the boat is 2,158N
Does sand stay sand forever?
Answer:
No sand doesn't stay sand forever.
Explanation:
We may have a thought that the sand we see on the beach areas are always the same one for eternal, but it is not true.Due to different activities like beach nourishment, sand replenishment etc. the sand in the beach areas are changed and replaced.If the sand remained there for long time, it also affects the sand eating organisms and plants.which description matches with which graph?
Answer:
Description 1 matches C.
Description 2 matches A.
Description 3 matches D.
Description 4 matches B.
Explanation:
Description 1 matches C. From graph C, we can see that the distance remains constant at a particular value. Hence, the car is not traveling and hence it is stopped.
Description 2 matches A. Speed is determined by the gradient of a distance-time graph. A depicts a linear graph which tells us that the gradient is constant and hence the car is at constant speed. The fact that the distance is increasing shows that the car is moving forward.
Description 3 matches D. Graph of D becomes less steeper as time progresses. This tells us that the gradient of the graph is decreasing and hence the speed of the car is decreasing.
Description 4 matches B. Graph B shows distance being decreased. This tells us that the car is coming back.
Suppose that you fill an ice-cube tray with water from the sink and put the trash in the freezer. The water’s temperature decreases because _________.
a. Cool air in the freezer flows into the water
b. Thermal energy flows out of the water into the air in the freezer
c. Water evaporates and moves into the air in the freezer
d. the water contracts at a lower temperature
I need help asap, thank you
b. Thermal energy flows out of the water into the air in the freezer
Explanation:
As we know that water has the freezing point in zero degree Celsius and the boiling point is in 100 degree Celsius.The process of freezing happens when water molecules reach a state where it can move because of the less temperature so it starts coming to each other and form a crystal structure. The process of forming a crystal structure happens due to the flow of thermal energy to the cold surrounding temperature. This is the same reason why you feel cold also.Gravity is a force between any two objects with mass. Why doesn't a person feel a gravitational force between him/herself and another person?
A) A person doesn't exert a gravitational force.
B) The two gravitational forces cancel each other out.
C) The gravitational forces of people is so small it is overshadowed by that of Earth.
D) There are so many people we are actually balanced by all the different gravitation
Answer:
C) The gravitational forces of people is so small it is overshadowed by that of Earth.
Select the correct answer from each drop-down
Two magnets are placed as shown in the
00
В
D
between the poles B and
. And the force of
between the poles A and DIS
Reset
Next
The force of repulsion between the poles B and C is minimum and the force of attraction between the poles A and D maximum.
Answer: Repulsion, Minimum, Attraction, Maximum
Explanation:
The Concept of attraction & Repulsion
The basic concept of attraction and repulsion between two similar and opposite poles of a bar magnet is that the ends of two bar magnets with similar strongly repel each other whereas poles of opposite polarity attract each other.
Since B and C are of opposite polarity, they will repel each other with minimum forces whereas A and D are of opposite polarity as well, hence they will attract each other with maximum forces when placed together.
We can flip the options accordingly saying, B and C will have the maximum attraction while A and D will have the minimum repulsion when placed together.
A bowling ball rolling at a certain speed has a kinetic energy of 12 J. What will be its new kinetic energy if it now rolls at 3 times the old speed?
The new kinetic energy of the bowling ball is 108 J,
Answer:
Explanation:
Any object in motion will experience an amount of kinetic energy. So the kinetic energy is directly proportional to the product of mass and square of velocity of the object. In the present case, the bowling ball is experiencing a kinetic energy of 12 J.
So, K.E. = 12 J = [tex]\frac{1}{2}mv^{2}[/tex]
As the ball will be having same mass, so when the velocity is increased three times of old velocity, so new speed will be 3v, where v is the old speed. Then the new kinetic energy will be as below:
New kinetic energy = [tex]\frac{1}{2}m(3v)^{2} = \frac{9}{2}mv^{2}[/tex]
Since we know that [tex]\frac{1}{2}mv^{2}[/tex] = 12 J, substitute this in new kinetic energy equation and we get
New kinetic energy = 9 × 12 J = 108 J.
Hence the new kinetic energy of the bowling ball is 108 J, when the new speed is three times the old speed,
Boyle's Law states that as the pressure on a gas increases at constant temperature the volume of the gas
A) Increases
B) Decreases
C) Stays the same
D) There is no relationship between pressure and volume
Boyle's Law states that the volume of a gas decreases as pressure increases at constant temperature. This is a fundamental concept in Chemistry.
Explanation:Boyle's Law, a fundamental principle in Chemistry and Physics, states that at a constant temperature, the volume of a gas is inversely proportional to the pressure applied on it. So, if the pressure on a gas increases and the temperature remains constant, the volume of the gas correspondingly decreases (Option B). In other words, if you squeeze a gas (increasing the pressure), it will take up less space (decreasing the volume), provided the temperature does not change.
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How Far East have you traveled if you ran 80 meters northeast
The student has traveled approximately 56.57 meters east.
In this case, the student has traveled 80 meters in a northeast direction. To determine how far east the student has traveled, we need to find the eastward component of their displacement.
Since the northeast direction can be broken down into equal north and east components, we can use trigonometry to determine the eastward displacement.
By using the sine function, we can find that the eastward displacement is approximately 56.57 meters.
A body that goes a distance and then returns to its starting point has the same beginning and ending points. In this case, the displacement is zero, but the distance travelled is not. It is possible to have zero, negative, or even positive displacements.
Therefore, the average velocity is usually 0 when the overall displacement is zero. To gain a better understanding, keep in mind that a body's displacement is a vector, meaning it depends on its direction. Its precise definition is the object's position change rate in a given direction.
An object is located 40.0 cm from a convex lens. The lens focuses light at a
distance of 10.0 cm. What is the image distance?
dof
Use the equation de
The image of distance (di) of the object is 13.33 cm.
Explanation:
Given data in the problem,
The object located at a distance from the convex lens.
do = 40.0 cm
The distance at which the light is focused.
f= 10.0 cm.
We need to find the image of distance di.
The lens equation gives the quantitative relation among the image distance (di), the object distance (do), and the focal length (f).
The equation is given by,
[tex]\frac{1}{f} =\frac{1}{di} +\frac{1}{do}[/tex].
[tex]\frac{1}{10} =\frac{1}{di} +\frac{1}{40}[/tex].
[tex]\frac{1}{10} -\frac{1}{40} =\frac{1}{di}[/tex].
[tex]\frac{4-1}{40}=\frac{1}{di}.\\[/tex]
[tex]\frac{3}{40} = \frac{1}{di}[/tex].
3 di=40.
di=[tex]\frac{40}{3}[/tex].
di = 13.33 cm
The image of distance (di) of the object is 13.33 cm.
A crane uses an average force of 5,200 N to lift a girder 25 m. How much work does the crane do on the girder?
Answer: 130000 J
Explanation: Work is the product of force and distance.
W = F x d
= 5200 N x 25 m
= 130000 J
The deepest mine ever drilled has a depth of 12300 meters. suppose you drop a rock with a mass of .12 kilograms down the shaft of this mine. What would the rock's kinetic energy be after falling 3200 meters? What would the potential energy associated with the rock be at that same moment? Assume no air resistance and a constant free-fall acceleration. (please show the equations used and why you used these equations.) Thank you.
Answer:
Correct answer: Ek = 384,000 J = 0.384 · 10⁶ J = 0.384 MJ
Ep = 1,092,000 J = 1.092 · 10⁶ J = 1.092 MJ
Et = 1,476,000 J = 1.476 · 10⁶ J = 1.476 MJ
Explanation:
The total energy at all times is equal to the sum of kinetic and potential energy.
Et = Ep + Ek
We will take the bottom of the mine as a reference point
We can solve this problem combined with the help of kinetics and energy conservation laws, or just with energy conservation laws, which I will do.
Before we drop a rock the potential energy is maximum and the kinetic energy is equals to zero.
The formula for calculating potential energy is:
Ep = m g h , we will take that g = 10 m/s²
This is the maximum potential energy (or total energy)
Epmax = Et = 12 · 10 · 12,300 = 1,476,000 J = 1.476 · 10⁶ J = 1.476 MJ
After a fall of 3,200 m the rock will be on height of 9,100 m and its potential energy will be:
Ep = m g h₁ = 12 · 10 · 9,100 = 1,092,000 J = 1.092 · 10⁶ J = 1.092 MJ
The difference between the maximum potential energy (or total energy) and the potential energy at height h₁ is actually kinetic energy.
Ek = ΔEp = Et - Ep = 1,476,000 J - 1,092,000 J
Ek = 384,000 J = 0.384 · 10⁶ J = 0.384 MJ
God is with you!!!
What is the kinetic energy of a 150 kg object moving at a velocity of 15 m/s?
25312.5 j
16875 j
50625 j
33750 j
Answer:16875joules
Explanation:
Mass=m=150kg velocity=v=15m/s
kinetic energy =(m x v^2)/2
Kinetic energy =(150x15^2)/2
Kinetic energy =(150x225)/2
kinetic energy =33750/2
Kinetic energy =16875joules
You are standing on a bathroom scale in an elevator that is not moving and it reads 600N. The elevator then moves upward at a constant velocity of 3.25 m/s. what does the scale read?
While the elevator is speeding up from zero to 3.25 m/s, the scale reads something more than 600N. But once the elevator settles into a constant speed ... whatever that is ... the scale settles back to 600N.
Acceleration is defined as a change in velocity over time. If a runner increases velocity
from 2 m/s to 4 m/s over a period of 20 seconds, what is her acceleration?
Answer:
a = 0,1[m/s^2]
Explanation:
First we need to indentify the initial data.
And using this kinematic equation we have:
[tex]v = 4[m/s]\\v_{0}= 2 [m/s] \\t = 20[s]\\\\v= v_{0}+a*t\\a=\frac{v-v_{0}}{t} \\a= \frac{4-2}{20} \\a=0.1[m/s^{2}][/tex]
Research the potential for a large earthquake off the coast of Oregon. What are two of the biggest concerns with a large earthquake in this area?
There is a 33% chance of a large earthquake off the coast of Oregon.
The two main concerns of a large earthquake are Gas fires and Tsunami .
Explanation:
Everytime a large earthquake hits in any other part of the world, We find a small earthquake hitting off the coast of Oregon.
So scientists feel that as United States is prone to Earthquakes, the people have to be prepared for such eventualities.
The main concern for this large earthquake is, that it might lead to gas leakages at homes that can start a gas fire, which might spread. So people have to be careful and check on any gas leakages.
Such large earthquakes can also lead to tsunami waves. So people have to take precautions and evacuate, if they are near the coastline.
Which statements describe the Mercalli scale? Check all that apply.
Which statements describe the Mercalli scale? Check all that apply. This scale measures seismic waves based on their size. This scale rates an earthquake according to how much damage it causes. This scale produces a single rating for earthquakes that reach the surface. This scale uses Roman numerals to rank the damage caused by an earthquake. This scale measures the magnitude of an earthquake based on the size of seismic waves.
This scale rates an earthquake according to how much damage it causes.
This scale uses Roman numerals to rank the damage caused by an earthquake.
Explanation:The intensities of the earthquake can be easily measured with the scale called The Mercalli intensity scale. The Scale called the Richter scale considers the energy of the earthquake. But the Mercalli scale will not consider the energy of the earthquake.
The effects of the earthquake is considered by the Mercalli scale and then the intensity of the earthquake will be calculated based on the effects that is being observed.It is a type of linear measurement. It uses the Roman numerals for the purpose of ranking the damages that are caused by the earthquake.
Answer:
This scale rates an earthquake according to how much damage it causes.
This scale uses Roman numerals to rank the damage caused by an earthquake.
Explanation:
Its CORRECT because I passed the test 100% on e d g e n u i t y 2020
if a star 100 light years from earth is beginning to expand into a giant star how long will it take for astronomers to observe this development explain
Final answer:
If a star 100 light-years away begins to expand, it will take 100 years for astronomers on Earth to observe the event, as light from the expansion will take that long to travel the distance to our planet.
Explanation:
If a star 100 light-years away from Earth is beginning to expand into a giant star, astronomers will observe this development after 100 years. This delay is because the light from that event will take 100 years to travel the distance from the star to Earth. As light is the fastest thing in the universe, moving at over 186,000 miles per second, it is the speed at which we receive information from the cosmos. So, even if the star began to expand today, we would not be aware of it until 100 years later - when the light showing the star's expansion arrives here. This concept is similar to observing galaxies through the universe, which allows us to see them as they were when the light left them, essentially looking back in time.
In this section of a circuit, a current of 2.5 A flows across R2. Find the current that flows across R3. Let R1= 3.0 ohm, R2= 8.0 ohm, and R3= 4.0 ohm
A. 2.5 A
B. 10 A
C. 6.7 A
D. 5.0 A