Question Detail

Energy posses by a body in motion is called

Kinetic Energy
Potential Energy
Both of Above
None of Above

Answer: Option A

1. 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.

2. unit of Pressure is

newton second
pascal
watt
newton per meter

Answer: Option B

Explanation:

newton second is unit of impulse,

watt is unit of Power,

newton per meter is unit of Surface Tension.

3. What is the relation between wavelength, frequency and velocity ?

velocity of wave = frequency * wavelength
velocity of wave = frequency/wavelength
velocity of wave = wavelength/frequency
None of above

Answer: Option A

4. Which of the following is an electromagnetic wave ?

Cathode rays
Sound wave
Ultrasonic wave
Infra red rays

Answer: Option D

5. Which instrument is used to measure sound under water ?

Hygrometer
Hygroscope
Hypsometer
Hydrophone

Answer: Option D

Explanation:

Hygrometer - is used to measure level of humidity,

Hygroscope - shows the changes in atmospheric humidity,

Hypsometer - is used to determine the boiling points of liquids.