Physics General Knowledge MCQs Quiz for Competitive Exams with Answers Set 7

Physics MCQs Quiz for Competitive Exams.This post contains Physics Objective Questions and Answers for NTS, PPSC, CSS, FPSC, PMS, OTS, PTS Tests and Interviews. These Objective Physics Questions and Answers are to prepare online competitive exams. MCQs are taken from Caravan Comprehensive GK Book.

1. During rusting ______ ?

(a) Iron gains weight
(b) Iron‘loses weight
(c) Weight of iron remains unchanged
(d) Iron volatilizes

2. When water boils, its temperature _______ ?

(a) Begins to increase
(b) Begins to decrease
(c) Remains constant
(d) Fluctuates

3. Rectifiers are used to convert ______ ?

(a) DC to AC
(b) AC to DC
(c) High voltage to low voltage
(d) Low voltage to high voltage

4. A needle smeared with vaseline when lowered slowly on the surface of the water in a horizontal position appears to float. The phenomenon is an example of ______ ?

(a) Capillary action
(b) Surface tension
(c) Osmosis
(d) Archimedes principle

5. Which one of the following statements is correct ?
A slab of ice kept in a room ________ ?

(a) Does not radiate heat
(b) Does not radiate heat but absorbs heat from the surrounding
(c) Radiates heat but absorbs more heat from the surrounding
(d) Radiates heat more than that absorbed by it from the surrounding

6. The phenomenon of the formation of three-dimensional image by the interference of two light beams from the laser or other coherent sources of light is called ?

(a) Opticai photography
(b) X-ray photography
(c) Radiography
(d) Holography

7. Paper becomes brittle and yellow with age, Why ?

1. The acid content in paper causes brittleness to develop
2. In the presence of visible light, photosensitised oxidation occurs
3. The ultra-violet component of sunlight causes photolysis of cellulose by direct cleavage of the cellulose polymer

(a) 1 and 2
(b) 2 and 3
(c) 1 and 3
(d) 1. 2 and 3

8. Two cars, passing each other at high speed, are in danger of side swiping because ______ ?

(a) Of the increase in air pressure in the space between them
(b) Of decrease in the velocity of air molecules between them
(c) Of decrease in air pressure in the space between them
(d) Increase in the velocity of air molecules between them

9. Which of the following is used as a coolant in nuclear reactors ?

(a) Heavy water
(b) Cadmium
(c) Liquid sodium
(d) Graphite

10. Which of the following is good nuclear fuel ?

(a) Uranium-238
(b) Neptunium-239
(c) Thorium-236
(d) Plutonium-239

11. In an atomic explosion, enormous energy is released which is due to the ______ ?

(a) Conversion of neutrons into protons

(b) Conversion of chemical energy into heat energy
(c) Conversion of chemical energy into nuclear energy
(d) Conversion of mass into energy

12. Optic fibres are mainly used for which of the following ?

(a) Communication
(b) Weaving
(c) Musical instruments
(d) Food industry

13. Which of the following take place when the subject speaks untruth while being tested by the polygraph instrument ?

1. His blood pressure goes up.
2. His pulse quickens.
3. His skin darkens.
4. He sneezes.

(a) 1 and 2
(b) 3 and 4
(c) 1, 2 and 3
(d) 2, 1 and 3

14. The following processes take place during the launching of a rocket ?

1. Rocketfuel is burnt.
2. Gases are produced.
3. The rocket moves in the forward direction.
4. Gases come out with momentum in the backward direction.
The correct sequential order in which the above processes occur is _________ ?

(a) 1, 2, 3, 4
(b) 1, 3, 2, 4
(c) 1, 2, 4, 3
(d) 1, 3, 4, 2

15. Aviation fuel for jet aeroplanes consists of purified ?

(a) Petrol
(b) Kerosene
(c) Gasoline
(d) Diesel

Physics General Knowledge MCQs Quiz for Competitive Exams with Answers Set 8

Physics General Knowledge MCQs Quiz for Competitive Exams with Answers Set 9