# Impulse Momentum Theorem and Impact - Mechanical Engineering (MCQ) questions and answers

1)   If two objects of 30 kg and 10 kg move with equal kinetic energy, then what is the ratio of magnitudes for linear momentum?

a. √3 : 1
b. 1 : √3
c. 1 : 3√3
d. 1 : 3
 Answer  Explanation ANSWER: √3 : 1 Explanation: No explanation is available for this question!

2)   What is the SI unit of linear momentum?

a. kg.m2 / sec
b. kg.m / sec
c. N.sec2
d. N.m.sec
 Answer  Explanation ANSWER: kg.m / sec Explanation: No explanation is available for this question!

3)   A ball is dropped on a horizontal surface from a height of 15 m. What will be the rebounding height of the ball after striking the surface? (coefficient of restitution = 0.8)

a. 9.6 m
b. 6.5 m
c. 5.6 m
d. Insufficient data
 Answer  Explanation ANSWER: 9.6 m Explanation: No explanation is available for this question!

4)   Which of the following laws derive impulse moment principle?

a. Newton's 3rd law
b. Newton's 2nd law
c. Newton's 1st law
d. All of the above
 Answer  Explanation ANSWER: Newton's 2nd law Explanation: No explanation is available for this question!

5)   What is the coefficient of restitution (e) for elastic impact?

a. e = 0
b. e = 1
c. e < 0
d. e > 1
 Answer  Explanation ANSWER: e = 1 Explanation: No explanation is available for this question!

6)   If coefficient of restitution is zero during plastic impact, then ___________

a. kinetic energy is conserved
b. momentum energy is conserved
c. bodies move away after impact
d. all of the above
 Answer  Explanation ANSWER: momentum energy is conserved Explanation: No explanation is available for this question!

7)   Coefficient of restitution is the ratio of impulse during __________

a. plastic deformation and elastic deformation
b. elastic deformation and plastic deformation
c. restoration period and deformation period
d. deformation period and restoration period
 Answer  Explanation ANSWER: restoration period and deformation period Explanation: No explanation is available for this question!

8)   The total momentum of a system __________, if no external impressed force acts on it.

a. increases
b. decreases
c. remains constant
d. none of the above
 Answer  Explanation ANSWER: remains constant Explanation: No explanation is available for this question!

9)   An object of 30 kg is moved with a velocity of 2 m/s on a horizontal smooth surface. What is the velocity of the block for 4 seconds if force of 40 N is applied on it in the direction of force?

a. 2 m/s
b. 4.6 m/s
c. 7.33 m/s
d. 9.33 m/s
 Answer  Explanation ANSWER: 7.33 m/s Explanation: No explanation is available for this question!

10)   If a body is subjected to plastic impact, _______

a. only kinetic energy is conserved
b. only momentum is conserved
c. both a. and b.
d. none of the above
 Answer  Explanation ANSWER: only momentum is conserved Explanation: No explanation is available for this question!