PG TRB Physics Previous Year Questions with Answer Key - 4

Question: 16

DC current can be controlled by which one of the following components?

(A) Impedance

(B) Capacitance

(C) Resistance

(D) Inductance

Question: 17

In a pressure cooker cooking is faster because the increase in vapour pressure

(A) increases the boiling point

(B) decreases the specific heat 

(C) increases the specific heat

(D) decreases the boiling point

Question: 18

The frequency of sound waves in the audible range is

(A) 1 Hz – 10 Hz

(B) 0.5 Hz – 5 Hz

(C) 20,000 Hz – 40,000 Hz

(D) 20 Hz – 20,000 Hz

Question: 19

White light is made up of seven colours. What is the method of separating the colours?

(A) By passing it through a prism

(B) By filtration

(C) Can’t be separated

(D) Both (a) and (b)

Question: 20

During the change of state the temperature of the substance

(A) increases

(B) decreases

(C) remains the same

(D) may increase or decrease