Question Detail

Solar cell converts

Sound energy into electrical energy
Electrical energy into mechanical energy
Solar energy into electrical energy
Electrical energy into light energy

Answer: Option C

1. 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

2. Marie and Pierre Curie invented

Radio
Radium
Radar
Refrigerator

Answer: Option B

Explanation:

Marie and Pierre Curie of France invented Radium in 1898,

Radio was invented by G. Marconi of England in 1901,

Radar was invented by Dr. A.H. Taylor and L.C. Young of USA in 1922,

Refrigerator was invented by J. Harrison and A. Catlin of Britain in 1834.

3. Which instrument is used to measure altitudes in aircraft's ?

Audiometer
Ammeter
Altimeter
Anemometer

Answer: Option C

Explanation:

Ammeter - Measures strength of electric current.

Audiometer - Measures intensity of sound.

Anemometer - Measures force and velocity of wind and directions.

4. Which instrument is used to record physical happenings at a distant place ?

Thermostat
Tonometer
Telemeter
Transponder

Answer: Option C

Explanation:

Thermostat - is used to regulate the temperature at a particular point.

Tonometer - is used to measure the pitch of a sound,

Transponder - is used to receive a signal and transmit a reply immediately.