Practice Questions with Answers - Multiple Choice Questions

MCQ Questions for Class 9 Science Chapter 11 Work and Energy

MCQ Questions for Class 9 Science Chapter 11 Work and Energy

 

Multiple Choice Questions

Question 1.
When a body falls freely towards the earth, then its total energy:
(a) increases
(b) decreases
(c) remains constant
(d) first increases and then decreases

Answer

Answer: (c) remains constant


Question 2.
In case of negative work, the angle between the force and displacement is:
(a) 0°
(b) 45°
(c) 90°
(d) 180°

Answer

Answer: (d) 180°


Question 3.
Water stored in a dam possesses:
(a) no energy
(b) electrical energy
(c) kinetic energy
(d) potential energy

Answer

Answer: (d) potential energy


Question 4.
Which one of the following is not the unit of energy?
(a) Joule
(b) Newton meter
(c) Kilowatt
(d) Kilowatt hour

Answer

Answer: (c) Kilowatt


Question 5.
A body is falling from a height h, After it has fallen a height \(\frac{h}{2}\), it will possess:
(a) only potential energy
(b) only kinetic energy
(c) half potential and half kinetic energy
(d) more kinetic and less potential energy

Answer

Answer: (c) half potential and half kinetic energy


Question 6.
The capacity of a body to perform work is called:
(a) Energy
(b) Work
(c) Power
(d) Heat

Answer

Answer: (a) Energy


Question 7.
The rate of work done is called:
(a) Energy
(b) Power
(c) Capacity
(d) All of these

Answer

Answer: (b) Power


Question 8.
The capacity to perform work is obtained from :
(a) Food
(b) Energy
(c) Power
(d) All of these

Answer

Answer: (b) Energy


Question 9.
An object of mass, m moving with velocity v has a kinetic energy of:
(a) \(\frac{1}{2} m v^{2}\)
(b) mgh
(c) \(\frac{2 m}{v^{2}}\)
(d) 2mv2

Answer

Answer: (a) \(\frac{1}{2} m v^{2}\)


Question 10.
The gravitational potential energy of an object of mass, m raised through a height, h from the earth’s surface is given by:
(a) \(\frac{1}{2}\) mv2
(b) mgh
(c) \(\frac{1}{2}\) mgh
(d) 2mgh

Answer

Answer: (b) mgh