How should the force applied on a body be varied with velocity to keep the power of force constant?a)Force should be inversely proportional to the square root of the velocity of the bodyb)Force should be inversely proportional to the velocity of the bodyc)Force should be directly proportional to the velocity of the bodyd)Force should not be varied. It should remain constant with the velocityCorrect answer is option 'B'. Can you explain this answer?

Question

Answer

We know that power (P) = force (F) x velocity (v).

Since the body is moving with acceleration,v changes and as a result of that P also changes,F being constant.

For P to be constant, F v = constant or F ∝ 1/v i.e

Force should be inversely proportional to the velocity of the body.

Thus,as v increases, F should decrease to keep P constant.

Answer

P= w/t.we know (w=F.S).p=FS/t.we know (s/t= v).p=F V.F=p/v.when power is constant .then force is inversely proportional to v.

Answer

See.. We know that Power is the dot product of Force and Velocity Vector and hence To keep Power Constant..If Velocity Increases, Force must be decreased and vice versa..Hence the Force Should be Inversely porportional to Velocity to keep Power Constant

Answer

See . Power = Energy/ time.Enery /work done= Force ×Displacement.So put value in  Power= Force × velocity.  If power is constant then force=1/velocity.

Answer

Force should be inversely proportional to the velocity of the body.

Explanation:
When a force is applied to an object, it does work on that object, and the rate at which work is done is known as power. Power is defined as the work done per unit time, and it is given by the equation:

Power = Work / Time

If we want to keep the power of the force constant, we need to ensure that the work done per unit time remains the same. Since work is equal to force multiplied by displacement, we can rewrite the equation for power as:

Power = (Force * Displacement) / Time

If we rearrange this equation to solve for force, we get:

Force = (Power * Time) / Displacement

Now, let's consider the velocity of the body. Velocity is defined as the rate at which an object changes its position. Mathematically, it is given by the equation:

Velocity = Displacement / Time

If we rearrange this equation to solve for displacement, we get:

Displacement = Velocity * Time

Substituting this value for displacement in the equation for force, we get:

Force = (Power * Time) / (Velocity * Time)

The time cancels out, leaving us with:

Force = Power / Velocity

Therefore, the force should be inversely proportional to the velocity of the body in order to keep the power of the force constant.

In simpler terms, as the velocity of the body increases, the force required to maintain a constant power decreases. This is because when an object moves faster, it covers more distance in a given time, so less force is needed to do the same amount of work in that time. Conversely, when the velocity decreases, more force is required to maintain the same power.

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