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a body is initially at rest it undergoes one dime...

Question:
A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

(i) t^½ (ii) t (iii) t^3/2 (iv) t²

Answer:

(ii) t

Mass of the body = m

Acceleration of the body = a

Using Newton's second law of motion, the force experienced by the body is given by the equation:

F = ma

Both m and a are constants.Hence, force F will also be a constant.

F = ma = Constant … (i)

For velocity v, acceleration is given as,

a = dv / dt = constant

dv = Constant x dt

v = αt ....... (ii)

where α is another constant

v ∝ t ......... (iii)

Power is given by the relation:

P = F.v

Using equations (i) and (iii), we have:

P ∝ t

Hence, power is directly proportional to time.

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Question:
A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

(i) t^½ (ii) t (iii) t^3/2 (iv) t²

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Question: A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to (i) t½ (ii) t (iii) t3/2 (iv) t2

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Question:
A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

(i) t^½ (ii) t (iii) t^3/2 (iv) t²