A ball of mass 0.1kg moving with a velocity of 20ms-1 is hit by a force which acts on it for 0.02s. If the ball moves off in the opposite direction with a velocity of 25ms-1 , calculate the magnitude of the force.
A
25N
B
125N
C
225N
E
100N
Verified Correct Answer: C.
Physical Principles & Numerical Solution
Impulse = \(\Delta\) momentum
F x t = m(V\(_2\) - V\(_2\))
F = \(\frac{M(V_1 - V_2)}{t}\) = \(\frac{0.1(-25 - 20)}{0.02}\) = \(\frac{- 4.5}{0.02}\) = - 225N
Therefore, the force = 225N
Source: Myschool Past Questions Archive (Record #43059)