Question Detail
Which unit we use to express Nuclear sizes ?
- Tesla
- Newton
- Fermi
- None of above
Answer: Option C
1. David Hughes invented
- Machine Gun
- Microphone
- Microscope
- Motorcycle
Answer: Option B
Explanation:
David Hughes of USA invented Microphone in 1878,
Machine Gun was invented by Richard Gatling of USA in 1861,
Microscope was invented by Z. Jansen of Netherlands in 1590,
Motorcycle was invented by Edward Butler of England in 1884.
2. 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.
3. Which instrument is used to measure changes in volume of substances ?
- Dyanamo
- Dilatometer
- Cyclotron
- Electroscope
Answer: Option B
Explanation:
Dyanamo - is used to convert mechanical energy into electrical energy,
Cyclotron - is a charged particle accelerator which can accelerate charged particles to high energies,
Electroscope - is used to detect the presence of an electric charge.
4. 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.
5. Which instrument is used to measure pressure of gases ?
- Manometer
- Machmeter
- Magnetometer
- Micrometer
Answer: Option A
Explanation:
Machmeter - is used to determine the speed of an aircraft in terms of speed of sound,
Magnetometer - is used to compare magnetic movements and fields,
Micrometer - is used to convert sound waves into electrical vibrations.