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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 ______.
Options
`t^(1/2)`
t
`t^(3/2)`
`t^2`
Solution
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 t.
Explanation:
∵ Acceleration a is constant and u = 0
∴ Force F = ma (is constant) and velocity at time t = ν = at
∴ Power delivered at time t
= P = Fν = (ma)at = (ma2)t
⇒ P ∝ t
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