Q1. Unit of distance used in navigation is
(a) Nautical mile
(b) Kilometre
(c) Light year
(d) Yard
(UPSC Prelims 1980)
Answer: (a) Nautical mile
Explanation: A nautical mile is the standard unit in marine and air navigation, equivalent to 1.852 kilometers, based on the Earth’s circumference.
Q2. Distance of stars is measured in(a) Light years
(b) Kilometres per second
(c) Kilometres only
(d) Nautical miles
(UPSC Prelims 1980)
Answer: (a) Light years
Explanation: Astronomers measure stellar distances in light years, which represent the distance light travels in one year, approximately 9.46 trillion kilometers.
Q3. Hygrometer is used to measure
(a) Density of a liquid
(b) Relative humidity of atmosphere
(c) Absorption power of plants
(d) Temperature of air
(UPSC Prelims 1982)
Answer: (b)
Explanation: A hygrometer measures the relative humidity in the atmosphere, which is the amount of moisture present in the air. It is essential in weather forecasting, agriculture, and climate studies.
Q4. Match List I with List II
| List I (Forms) | List II (Quantities) |
|---|---|
| (A) Cusec | (1) Pressure |
| (B) Byte | (2) Intensity of earthquakes |
| (C) Richter | (3) Rate of flow |
| (D) Bar | (4) Computer memory |
Select the correct answer:
(a) 4 1 2 3
(b) 2 4 3 1
(c) 3 4 2 1
(d) 3 2 1 4
Answer: (c)
Explanation:
Cusec is a unit used to measure the rate of flow of water, hence A-(3).
Byte is a unit of computer memory, making B-(4) correct.
Richter scale measures the intensity of earthquakes, confirming C-(2).
Bar is a unit of pressure, validating D-(1).
Therefore, the correct sequence is 3 4 2 1.