Question

5) A body at rest when acted upon by a force 'F' moves with an acceleration 'a' for time 't'. Show that the power spent on the body is given by aFt. b) Two boys of equal weights take 20 s and 30 s respectively to climb a small hill. Find the ratio of powers possessed by them. c) Convert the energy of 1.6 X 10 Jinto ev. Please give the correct and whole answer​

Answer 1

Answer:

Here is ur answer dear

Explanation:

Let us find the kinetic energy acting on the body. As it is given in the question that the body acquired a velocity v, the total energy of the body is equal to the kinetic energy of the body,

Kinetic energy of the body is equal to,

K.E=12mv2...(1)K.E=12mv2...(1)

Also, the force acting on the body is equal to,

F=ma⇒m=Fa...(2)F=ma⇒m=Fa...(2)

As the mass of the body is not given in question, substitute equation 2 in equation 1, we greet,

K.E=12×Fa×v2⇒K.E=Fv22aK.E=12×Fa×v2⇒K.E=Fv22a

As, the work done by a body is equal to the change in kinetic energy of the body according to the work-energy theorem,

W=ΔK.EW=Fv22aW=ΔK.EW=Fv22a

Hence, the above is the formula for work done in known terms.

I hope it's help you