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?
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.