1691. An electric current can produce :
A. Chemical effect
B. Magnetic effect
C. Heatin effect
D. All of the above *
1692. The unit of home electricity energy consumption is :
A. Watt hour
B. Kilowatt hour *
C. Joule hour
D. None of them
1693. The magnet always points in the same direction, if allowed to move freely That is towards north and south poles because of :
A. Gravitational field
B. A lot of metal deposits on north and south poles
C. As a result of the north pole’s attraction and the western pole’s repulsion
D. Earth is huge magnet *
1694. When sound is reflected from floor, ceiling or a wall , it mixes with the original sound and changes its complexation , it is called as :
A. Sound
B. Echo
C. Reverberation *
D. Noise
1695. The speed of sound in dry air at 20 degree centigrade is about :
A. 130 meters per second
B. 230 meters per second
C. 330 meters per second *
D. 430 meters per second
1696. The speed of light in vacuum :
A. 300 million meters per second *
B. 300 million meters per hour
C. 300 million kilometers per second
D. None of these
1697. The time, light takes from the sun to reach earth is :
A. 8 Minutes *
B. 25 Minutes
C. 45 Minutes
D. 48 Minutes
1698. Light from the sun travels a distance before it reaches the earth :
A. 50 million km
B. 100 million km
C. 150 million km *
D. 200 million km
1699. The most suitable thermometer for measuring the boiling point of water is :
A. Mercury thermometer *
B. Alcohol thermometer
C. Bimetallic thermometer
D. None of them
1700. The density of water is greatest at :
A. – 30 Degree centigrade
B. 0 Degree centigrade
C. 4 Degree centigrade *
D. None of them