Question

an object of mass M initially at rest under the action of constant force f attains a velocity V in time T the average power supplied to the mass is

Answer 1

Mv^2/2t  Avg power=w/2t W=f*d F=m*v/t W=m*v/t*v*t/2t Mv^2/2t Answer

Answer 2

Answer:

Given that the mass of the object is ‘m’; its initial velocity ‘u’ is zero and with the action of constant Force ‘F’ the final velocity ‘v’ attained at time ‘t’.  

Therefore, we know that Power = work/time

Let us consider the mass of the object with initial velocity and final velocity, so

             $P\quad =\quad \frac { (P1+P2) }{ 2 } \\ =\quad \frac { [F(0)+F(v)] }{ 2 } \\ =\quad F\frac { v }{ 2 } \\ =\quad [\frac { m(v-0) }{ t } ]\frac { v }{ 2 } \\=\quad (\frac { 1 }{ 2 } )m\frac { { v }^{ 2 } }{ t }$

Therefore the average power that is supplied to mass ‘m’ is $(\frac { 1 }{ 2 } )m\frac { { v }^{ 2 } }{ t }$