Question Detail
unit of Pressure is
- newton second
- pascal
- watt
- newton per meter
Answer: Option B
Explanation:
newton second is unit of impulse,
watt is unit of Power,
newton per meter is unit of Surface Tension.
1. 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.
2. Which instrument is used to measure the scattering of light by particles suspended in a liquid ?
- Nephetometer
- Ohmmeter
- Ondometer
- Pyrometer
Answer: Option A
Explanation:
Ohmmeter - is used to measure electrical resistance in ohms,
Ondometer - is used to measure frequency of electromagnetic waves,
Pyrometer - is used to measure very high temperature.
3. 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.
4. 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
5. The force which opposes the relative motion between different layers of liquid or gases is called
- Critical Velocity
- Streamline Flow
- Terminal Velocity
- Viscous Force
Answer: Option D
Explanation:
Critical Velocity - The maximum velocity upto which fluid motion is streamline is called Critical Velocity.
Streamline Flow - If velocity of all fluid particles is same all the time then it can be said in streamline flow.
Terminal Velocity - When a body falls in viscous medium, its velocity first increases and finally becomes constant. The constant velocity is called terminal velocity.