Question: Fathom is the unit of marine depth. One Fathom is equal to
1. 5 feet
2. 7 feet
3. 10 feet
4. 6 feet
Answer: 4
Question: In which metal corrosion takes place soon?
1. Iron
2. Copper
3. Gold
4. Brass
Answer: 1
Question: Radio telescopes are better than optical telescopes because
1. They can detect faint galaxies which cannot be done by optical telescopes.
2. They can work even in cloudy conditions.
3. They can work during the day and night.
4. All of the above
Answer: 4
Question: A transformer is used to
1. increase A.C. voltage.
2. increase D.C. voltage.
3. convert electrical energy to heat energy.
4. convert A. C. energy to D.C. energy.
Answer: 1
Question: A device used for converting a.c. into d.c. is called
1. Transformer
2. Rectifier
3. Dynamo
4. Induction oil
Answer: 2
Question: The atmosphere is heated mainly by
1. Insolation
2. Conduction
3. Radiation
4. Convection
Answer: 4
Question: The hardest substance known is
1. Diamond
2. Steel
3. Platinum
4. Tungsten
Answer: 1
Question: Is the microphone used for Public Address System,
1. Sound waves are converted into electric signals
2. Sound waves are directly transmitted
3. Electric signals are first converted into sound waves
4. Amplification is not required at all
Answer: 1
Question: Which electromagnetic radiation is used for satellite communication?
1. Ultraviolet
2. Infrared
3. Microwave
4. Millimeter wave
Answer: 3
Question: Solar cells work on the principle of
1. Photovoltaic effect
2. Photoelectric effect
3. Photoconductive effect
4. Photosynthesis
Answer: 1
Question: A person presses the earth least when he is
1. Standing
2. Sitting
3. Running
4. Lying on the ground
Answer: 4
Question: On a cold morning, a metal surface will feel colder to touch than a wooden surface because metal has
1. High thermal conductivity
2. High specific heat
3. Low thermal conductivity
4. Low specific heat
Answer: 1