 General Knowledge Quiz for CDS 2020(Work, Power and Energy): 20th Jan 2020

Jai Hind Aspirants, Defence Adda is providing you all with this quiz on General Knowledge questions for CDS, AFCAT, CAPF and other Defence Examinations. The questions asked in General Knowlegde Section  are based on the topics from History, Polity, Geography, Economics and General Science. We will provide you Important Questions on daily basis so that it becomes easy for you to crack written exam and get call letter for SSB Interview.

Q1. With which among the following physical quantities, “Work” shares same the same unit?

(a) Force
(b) Acceleration
(c) Power
(d) Energy

Q2. The work done by gravity on a freely falling body is ________________.

(a) Negative
(b) Positive
(c) Zero
(d) Can’t be determined

Q3. What kind of energy makes bullet to pierce the wooden target?

(a) Potential Energy
(b) Mechanical Energy
(c) Frictional Energy
(d) Kinetic Energy

Q4. If the velocity of a body is reduced by half, then its kinetic energy will _________.

(a) reduces by a factor of 1/4
(b) increases by a factor of 4
(c) decreases by a factor of 4
(d) reduces by a factor of 4

Q5. One Horsepower (1 H.P.) is equal to __________ watt.

(a) 746
(b) 786
(c) 756
(d) 766

Q6. Which among the following converts mechanical energy into electrical energy?

(a) Photo cell
(c) Motor
(d) Dynamo

Q7. The capacity of doing work developed in a body due to its position or configuration is called __________.

(a) Potential Energy
(b) Kinetic Energy
(c) Mechanical Energy
(d) Electrical Energy

Q8. A flying airplane has _________ energy.
1. Potential
2. Kinetic

(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) None of the above

Q9. Power is a ________ quantity.

(a) Scaler
(b) Vector
(c) Tensor
(d) None of the above

Q10. When a body moves in a circular motion, the work done by centripetal force is __________.

(a) Constant
(b) Positive
(c) Negative
(d) Zero

Solutions

S1. Ans.(d)
Sol. The SI unit of “Work” is Joule. Energy has the same unit.

S2. Ans.(b)
Sol. On a freely falling body, the work is done by the acceleration due to gravity is positive.

S3. Ans.(d)
Sol. The moving bullet has high amount of kinetic energy due to its very high speed. It hence pierce the wooden target due to its kinetic energy.

S4. Ans.(a)
Sol. Kinetic energy of a moving body is inversely proportional to the square of the velocity. Hence, if velocity of the body is reduced by half then kinetic energy of the body is reduced by the factor of ¼.

S5. Ans.(a)
Sol. One Horsepower is equal to 746 watt.

S6. Ans.(d)
Sol. Dynamo converts mechanical energy into electrical energy.

S7. Ans.(a)
Sol. The capacity of doing work developed in a body due to its position or configuration is called Potential Energy.

S8. Ans.(c)
Sol. A flying airplane has both potential (by virtue of its height) as well as kinetic (by virtue of its motion) energy.

S9. Ans.(a)
Sol. Power is a scaler quantity.

S10. Ans.(d)
Sol. For a body moving in a circular path, the centripetal force and the displacement are perpendicular to each other. So, the work done by the centripetal force is zero.  