Physics Practice Tests – Friction (Questions with Answers and Explanations)

A parachute attains a terminal velocity when _____ (JAMB 1998)

A. its density is equal to the density of air
B. the viscous force of the air and the upthrust completely counteract its weight
C. it expands as a result of reduced external pressure
D. the viscous force of the air is equal to the sum of the weight and upthrust.

A crate of mass 25 kg moving with a speed of 3 ms-1 on a rough horizontal floor is brought to rest after sliding a distance of 2.5 m on the floor. The coefficient of sliding friction between the crate and the floor is _____

A. 0.09
B. 0.18
C. 0.36
D. 0.54

Which of the following statements are TRUE about frictional force? (JAMB 1995)

I. It is always a disadvantage
II. It is sometimes a disadvantage
III. It always exists where there is a relative motion of two bodies that are in contact
IV. It is sometimes very useful

A. I and III only
B. I and IV only
C. II and III only
D. II and IV only

A body is released from rest at the top of a plane inclined at 30^o to the horizontal and 4.0 m high. If the coefficient of friction between the body and the plane is 0.3, calculate the time the body takes to reach the bottom of the plane. (WASSCE 2017)

A. 5.27 s      B. 6.67 s     C. 2.58 s      D. 1.57 s

The coefficient of friction between two perfectly smooth surfaces is _____ (JAMB 2013)

A. zero   B. infinity   C. one    D. half