Question Detail

What is newton third law of motion ?

Every body maintains its initial state rest or motion unless no external force is applied.
The rate of change in momentum of a body is directly proportional to the applied force on the body and takes place in the direction of force.
To every action there is equal and opposite reaction.
None of above.

Answer: Option C

Explanation:

Newton First Law of Motion : Every body maintains its initial state rest or motion unless no external force is applied.

Newton Second Law of Motion : The rate of change in momentum of a body is directly proportional to the applied force on the body and takes place in the direction of force.

1. Harry Brearley has invented

Electric iron
Electromagent
Stainless Steel
Gramophone

Answer: Option C

Explanation:

Harry Brearley of England has invented Stainless Steel in 1913,

Electric iron has been invented by H.W. Seeley of USA in 1882,

Electromagent has been invented by W.Sturgeon of England in 1824,

Gramophone has been invented by T.A. Edison of USA in 1878.

2. 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.

3. Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings."

Doppler's Effect
Newton's law of cooling
Kirchhoff's Law
Stefan's Law

Answer: Option B

Explanation:

Doppler's Effect - The Doppler effect can be described as the effect produced by a moving source of waves in which there is an apparent upward shift in frequency for observers towards whom the source is approaching and an apparent downward shift in frequency for observers from whom the source is receding.

Kirchhoff's Law - Kirchhoff's Law signifies that good absorbers are good emitters.

Stefan's Law - The radiant energy emitted by a black body per unit area per unit time is directly proportional to the fourth power of its absolute temperature.

4. Name of the instrument to measure atomspheric pressure ?

Barometer
Barograph
Bolometer
Callipers

Answer: Option A

Explanation:

Barograph - Recordings of atmospheric pressure,
Bolometer - Used to measure heat radiation,
Callipers - Used to measure inner and outer diameters of bodies.