light, heat, thermodynamics, wave motion, sound, optics & oscillations - Category wise Question and Answer Practice Test with Solutions

Question : 1

Match list I with list II and select the correct answer using the codes given below the lists.

a) A – 3, B – 4, C – 2, D – 1

b) A – 2, B – 3, C – 4, D – 1

c) A – 2, B – 1, C – 4, D – 3

d) A – 3, B – 4, C – 1, D – 2

Question : 2 [NDA]

Why is sound heard with more intensity through CO₂ than through the air ?

a) Density of CO₂ is less than that of air

b) Density of CO₂ is more than that of air

c) Air is bad conductor of heat

d) CO₂ is a compound, but air is a mixture of gases.

Question : 3 [UPPCS (Mains) 2011]

Decibel unit is used to measure

a) Sound intensity

b) Magnitude of earthquake

c) Light intensity

d) None of the above

Question : 4 [IAS Prelim]

Assertion (A) :
A piece of copper and a piece of glass are heated to the same temperature. When touched, thereafter, the copper piece appears hotter than the glass piece.
Reason (R) :
The density of copper is more than that of glass.

a) Both A and R are true but R is not a correct explanation of A

b) Both A and R are true and R is the correct explanation of A

c) A is true but R is false

d) A is false but R is true

Question : 5 [PSC (Pre) 2017]

Assertion and Reason are given below.
Assertion (A):
We prefer the white dress in winters.
Reason (R):
White dresses are good reflectors of heat.
Which one among these is the right answer.

a) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

b) (A) is true, but (R) is false

c) Both (A) and (R) are true and (R) is the correct explanation of (A)

d) (A) is false, but (R) is true