If a 2 kg object is constantly accelerated from 0m/s to 16 m/s over 9 s, how much power musy be applied at t= 1 ?

1 Answer
Jan 3, 2016

The power needed is 6 26/81W or about 6.32W

Explanation:

When a force F is applied to an object moving at velocity v parallel to the force, the power needed is P=Fv.

The acceleration is a=(Deltav)/(Deltat)=(16m/s-0m/s)/(9s-0s)=16/9m/s^2

According to Newton's 2nd law the force is F=ma=2kg*16/9m/s^2=32/9N

Velocity at t=1s is v=at=16/9m/s^2*1s=16/9m/s and the power at this moment is P=Fv=32/9N*16/9m/s=512/81W=6 26/81W~~6.32W