If a rock is pushed by a boy with a force of 10N and that causes the rock to move with constant velocity for 5s, if there is 400W of power consumed, with what velocity will the rock move?

Answer 1

To find the velocity at which the rock moves, we can first calculate the work done on the rock by the boy.

Work = Force x Distance
Work = 10N x Distance (since the force is applied for 5s and the rock moves with constant velocity)
Work = 50N

Since Power is given as 400W and Power = Work / Time, we can find the time taken to do 50J of work with 400W of power.

Time = Work / Power
Time = 50J / 400W
Time = 0.125s

Therefore, the velocity at which the rock moves can be calculated by dividing the distance (work done) by the time taken, which is 50J/0.125s = 400m/s.

Hence, the rock will move at a velocity of 400m/s.