Physics Practice Tests – Newton’s Law of Motion (Questions with Answers and Explanations)

A body of mass 2kg moving vertically upwards has its velocity increased uniformly from 10 ms^-1 to 40 ms^-1 in 4s. Neglecting air resistance, calculate the upward vertical force acting on the body. [g = 10 ms^-2] (JAMB 1997) 

A. 15 N       B. 20 N      C. 35 N       D. 45 N

An object of mass 2 kg moving with a velocity of 3 ms^-1 collides head-on with another object of mass 1 kg moving in the opposite direction with a velocity of 4 ms^-1. If the objects stick together after collision, calculate their common speed.

A. 0.60 ms^-1     B. 0.67 ms^-1     C. 2.00 ms^-1     D. 3.33 ms^-1

A constant force of magnitude F acts on an object of mass 0.04kg initially at rest at a point O. If the speed of the object when it has moved 50 m from point O is 500ms^-1, what is the value of F? (JAMB 1986) 

A. 0.4 N       B. 100. 0 N        C. 250.0 N        D. 1000.0 N

Fuel was consumed at a steady rate of 5.0 x 10^-2 kg per second in a rocket engine and ejected as a gas with a speed of 4 x 10³ ms^-1. Determine the thrust on the rocket.

A. 20 N     B. 80 N     C. 200 N     D. 800 N

A body of mass 5 kg moving with a velocity of 10 ms^-1 collides with a stationary body of mass 6 kg. If the two bodies stick together and move in the same direction after the collision, calculate their common velocity.

A. 4.55 ms^-1     B. 12.00 ms^-1     C. 30.00 ms^-1     D. 50.00 ms^-1