6.9 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 ^1/2 (ii) t (iii) t ^3/2 (iv) t ²

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Payal Gupta | Contributor-Level 10

9 months ago

6.9 Let us assume

Body mass = m

Acceleration = a

According to Newton's 2nd law F = MA (constant)

We know a = dv/dt = constant. Hence dv = dt $*$ constant

On integrating, v = t + constant

The relation of power is given by P = F $* v$

We have $v = u + a t$

Hence, $P = F * (u + a t)$

= $m a (u + a t)$

= $m a u + m a^{2} t$

Therefore P $? t$

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6.9 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 1/2 (ii) t (iii) t 3/2 (iv) t 2

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6.9 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 ^1/2 (ii) t (iii) t ^3/2 (iv) t ²