Question Detail

If no external force acts on a system of bodies, the total linear momentum of the system of bodies remains constant. Which law states this ?

Newton first law
Newton second law
Newton third law
Principle of conservation of linear momentum

Answer: Option D

1. 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.

2. When a body is immersed partly or wholly in a liquid, there is an apparent loss in weight of the body which is equal to the weight of liquid displaced by the body.

True
False

Answer: Option A

Explanation:

TRUE, it is Archimedes Principle.

3. What is unit of Astronomical distance ?

light year
angstrom
weber
lux

Answer: Option A

Explanation:

angstrom is used to measure wave length,

weber is used to measure Magnetic flux,

lux is used to measure Intensity of illumination.

4. All planets move around the sun in elliptical orbits, with the sun being at rest at one focus of the orbit.

True
False

Answer: Option A

5. newton is used to measure

Speed
Volume
Force
Area

Answer: Option C