Question Detail

Which instrument is used in submarine to see the objects above sea level ?

Pykometer
Polygraph
Photometer
Periscope

Answer: Option D

Explanation:

Pykometer - used to determine the density and coefficient of expansion of liquids,

Polygraph - used to record changes in heartbeat, blood-pressure and respiration,

Photometer - used to compare luminous intensity of the source of light.

1. Radiocarbon is produced in the atmosphere as a result of

collision between fast neutrons and nitrogen nuclei present in the atmosphere
action of ultraviolet light from the sun on atmospheric oxygen
action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere
lightning discharge in atmosphere

Answer: Option A

2. Orbital speed of a satellite is dependent of its mass.

True
False

Answer: Option B

Explanation:

Orbital speed of a satellite is independent of its mass.

3. Which law is also called law of inertia ?

Newton first law
Newton second law
Newton third law
All of above

Answer: Option A

4. What is escape velocity ?

Escape velocity is the maximum velocity with which a body should be projected from the surface of earth so it do not go beyond gravitational field of earth.
Escape velocity is the minimum velocity with which a body should be projected from the surface of earth so it do not go beyond gravitational field of earth.
Escape velocity is the minimum velocity with which a body should be projected from the surface of earth so as it goes out of gravitational field of earth and never return to earth.
Escape velocity is the maximum velocity with which a body should be projected from the surface of earth so as it goes out of gravitational field of earth and never return to earth.

Answer: Option C

5. What are audible sound waves ?

Having frequency less than 20 Hz
Having frequency between 20 Hz to 20000 Hz
Having frequency more than 20000 Hz
None of above

Answer: Option B