Question

a body of mass m accelerates uniformly from rest to velocity v1 in time interval T1 . the instantaneous power delivered to the body as a funcyion of time t iis.

1) mv12 t/T12

2) mv1 t/T12

3) (mv1)2 t/t12

4) mv12 t2 /T1

Answer 1

1 is the correct option.......
hope it helps u.......

Answer 2

Answer: The instantaneous power is $P = m v_1^2 t / t_1^2$

According to the given data, we may assume the variable as their denotation.

Apply the first motion equation to get the value of acceleration, where u = 0  as it starts from rest, we will get,

                  $=> v = u + at \\=> v_1 = 0 + a t_1 \\=> a = v_1 / t_1.$

For any instance of time, the velocity be v = at and so it can be rewritten as

                  $- v = v_1 / t_1 t.$

Therefore, Power will be

                   $- P = F \times v = m a v \\=> P = m ( v_1/ t_1) ( v_1 /t_1 \times t) \\=> P = m v_1^2 t / t_1^2$