Question

For how long should a force of 100 N act on a body of mass 20 kg so that it acquires a velocity of 100 ms^-1?

Answer 1

Initial velocity of body = 0 ms^-1.
Final velocity of body = 100 ms^-1.
Mass of body = 20 kg.
Force applied = 100N.
We know that
F X t = m (v - u)
100 t = 20 (100 -0)
T = 2000/100 = 20 s.