Question Detail

Which instrument is used to measure the power of electric circuit ?

Voltmeter
Wattmeter
Wavemeter
Viscometer

Answer: Option B

Explanation:

Voltmeter - is used to measure electric potential difference between two points,
Wavemeter - is used to measure the wavelength of a radiowave,
Viscometer - is used measure viscosity of liquid.

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. Atmospheric pressure is measured by

Tonometer
Pyrometer
Barometer
Thermometer

Answer: Option C

3. 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

4. Which instrument is used to measure depth of ocean ?

Galvanometer
Fluxmeter
Endoscope
Fathometer

Answer: Option D

Explanation:

Galvanometer - measures electric current,
Fluxmeter - measures magnetic flux,
Endoscope - used to examine internal parts of the body.

5. Light year is a unit of

Time
Light
Distance
Intensity of light

Answer: Option C