Question Detail

Which instrument is used to determine the intensity of colours ?

Cathetometer
Chronometer
Colorimeter
Commutator

Answer: Option C

Explanation:

Cathetometer - is used to determine heights,

Chronometer - is used to longitude of a vessel at sea,

Commutator - is used to convert AC to DC.

1. Which instrument is used to measure pressure of gases ?

Manometer
Machmeter
Magnetometer
Micrometer

Answer: Option A

Explanation:

Machmeter - is used to determine the speed of an aircraft in terms of speed of sound,

Magnetometer - is used to compare magnetic movements and fields,

Micrometer - is used to convert sound waves into electrical vibrations.

2. The incident ray, reflected ray and normal to the reflecting surface at the incident point all never lie in same plane.

True
False

Answer: Option B

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. newton is used to measure

Speed
Volume
Force
Area

Answer: Option C

5. 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.