Work and Energy – Questions and Answers

Work and Energy – Questions and Answers for CBSE Class 9

1-Following is closely related to work

(A) Energy

(B) Power

(C) both (A) and (B)

(D) None of the above

 

2-The condition(s) need to be satisfied for work to be done

(A) the object must be displaced

(B) a force should act on an object

(C) both (A) and (B)

(D) the object must be stationary

 

3-We define work to be equal to the product of the

(A) Force and displacement

(B) Force and acceleration

(C) Pressure and displacement

(D) Pressure and acceleration

 

4-Work has

(A) magnitude and direction

(B) only magnitude and no direction

(C) only direction and no magnitude

(D) neither direction nor magnitude

 

5-Unit of work is

(A) Newton meter

(B) Newton / meter

(C) Newton

(D) None of the above

 

6-One ___ is the amount of work done on an object when a force of one ___ displaces it by one ___ along the line of action of the force.

(A) Joule, Newton, Meter

(B) Newton, Joule, Meter

(C) Joule, Meter, Newton

(D) Newton, Meter, Joule

 

7-Following is the biggest natural source of energy to us.

(A) Wind

(B) Water

(C) Sun

(D) None of the above

 

8-Capacity to do work is known as

(A) Force

(B) Pressure

(C) Energy

(D) Power

 

9-Unit of energy is

(A) Joule

(B) Newton

(C) Newton / Meter

(D) Newton / Kilogram

 

10-Mechanical Energy is equal to

(A) Kinetic Energy – Potential Energy

(B) Potential Energy – Kinetic Energy

(C) Potential Energy + Kinetic Energy

(D) None of the above

 

11-Kinetic Energy is the energy possessed by an object due to its

(A) Material

(B) Motion

(C) Height

(D) All of the above

 

12- The potential energy possessed by the object is the energy present in it by virtue of its

(A) motion

(B) position

(C) material

(D) shape

 

13-The law of conservation of energy is valid in

(A) all situations

(B) all kind of transformations

(C) both (A) and (B)

(D) none of the above

 

14-The rate of transfer of energy is known as

(A) work

(B) power

(C) kinetic energy

(D) potential energy

 

15-Power is given by

(A) Work / time

(B) Work x time

(C) Force / time

(D) Force x time

 

16-The unit of power is

(A) Joule Second

(B) Joule / Second

(C) Newton Second

(D) Newton / Second

 

17-One kilowatt hour (kW h) is equal to

(A) 3.6 x 10³ J

(B) 3.6 x 10⁴ J

(C) 3.6 x 10⁵ J

(D) 3.6 x 10⁶ J

 

18-The commercial unit of energy is

(A) kW h

(B) Joule

(C) Watt

(D) Newton

 

ANSWERS:

1-(C), 2-(C), 3-(A), 4-(B), 5-(A), 6-(A), 7-(C), 8-(C), 9-(A), 10-(C), 11-(B), 12-(B), 13-(C), 14-(B), 15-(A), 16-(A), 17-(D), 18-(A)