# [Set-1] Physics MCQ for Competitive Exams

Physics MCQs for competitive exams, class 9 and Class 10

Instruction: Click or hover the mouse button on the black box to view answer of the MCQs. For mobile users, just touch on the black box.

`[MCQ-1]` The layer of the atmosphere which control earth’s normal temperature is

A: Troposphere
B: Stratosphere
C: Mesosphere
D: Exosphere

`MCQ-2` When a water bubble comes up from the depth of a pond its volume

A: Increase
B: Decrease
C: first increase and then decrease
D: first decrease and then increase

`MCQ-3` Vapour density of a diatomic gas is 14. Atomic weight of the gas is

A: 14
B: 28
C: 42
D: 7

`MCQ-4` Two iron rods of length 1m and 2m respectively when heated to a certain temperature the ratio of linear expansion of those two rods will be

A: 1:2
B: 1:4
C: 1:8
D: 2:1

`MCQ-5` The deviation of light ray when refracted by a parallel glass slab is

A: 90 o
B: 0o
C: 45o
D: 180o

`MCQ-6` The frequency of DC is

A: 0 Hz
B: 50 Hz
C: 60 Hz
D: 220 Hz

`MCQ-7` β ray is represented by

A: 4He22+
B: 0e-1
C: p+1
D: n0

`MCQ-8` How gave the idea of modern periodic table?

A: Bohr
B: Mendeleev
C: Lothar Meyer
D: Moseley

`MCQ-9` Which of the following conducts electricity?

A: CaO
B: CH4
C: C2H2
D: C2H4

`MCQ-10` A Convex lens of focal length 10 cm. An object is kept 20 cm apart from the lens. The linear magnification of the image will be