Questions Answers For All Chapters – Geography Class 8
Humidity and Clouds
Q 1. Match the column and complete the chain:
A B C
(A) Cirrus (i) Vertical extent in the sky (a) Roaring clouds
(B) Cumulonimbus (ii) higher altitude (b) Floating clouds
(C) Nimbostratus (iii) Medium altitude (c)continuous rainfall
(D) Alto-cumulus (iv) Low altitude (d) snow flake clouds
Answer:
| A | B | C |
|---|---|---|
| (A) Cirrus | (ii) Higher altitude | (d) Snowflake clouds |
| (B) Cumulonimbus | (i) Vertical extent in the sky | (a) Roaring clouds |
| (C) Nimbostratus | (iii) Medium altitude | (c) Continuous rainfall |
| (D) Alto-cumulus | (iv) Low altitude | (b) Floating clouds |
Q 2. Choose the correct word from the brackets and complete the sentence:
(Cumulonimbus, Relative humidity, Absolute humidity, Condensation, Vapour-holding capacity)
(a) The ———————–of air is dependent on the temperature of air.
Answer: (a) The vapour-holding capacity of air is dependent on the temperature of air.
(b) The amount of vapour in 1 cu.m. of air shows the ———————–.
Answer: (b) The amount of vapour in 1 cu.m. of air shows the absolute humidity.
(c) As ——————– is less in desert areas, the air is dry there.
Answer: (c) As relative humidity is less in desert areas, the air is dry there.
(d) —————–type of clouds are indicators of storm.
Answer: (d) Cumulonimbus type of clouds are indicators of storms.
(e) In a free environment, the ————— of the vapour present in the atmosphere takes place around dust particles.
Answer: (e) In a free environment, the condensation of the vapour present in the atmosphere takes place around dust particles.
Q3: Differentiate between
(a) Humidity and Clouds:
Answer:
| Humidity | Clouds |
|---|---|
| The amount of water vapor in the air. | Clouds are formed when water vapor condenses at higher altitudes. |
| It determines the moisture content in the air. | It consists of tiny water droplets or ice particles. |
| High humidity increases chances of cloud formation. | Clouds influence weather patterns. |
(b) Relative Humidity and Absolute Humidity:
Answer:
| Relative Humidity | Absolute Humidity |
|---|---|
| Expressed as a percentage of the total moisture air can hold at a given temperature. | The actual amount of water vapor in 1 cu.m. of air. |
| Depends on temperature. | Not affected by temperature. |
| Example: 50% relative humidity means the air holds half the moisture it could at that temperature. | Example: 10 gms of water vapor in 1 cu.m. of air. |
(c) Cumulus Clouds and Cumulonimbus Clouds:
Answer:
| Cumulus Clouds | Cumulonimbus Clouds |
|---|---|
| Dome-shaped and indicate fair weather. | Tall, dense, and bring thunderstorms. |
| Found at 500m to 6000m altitude. | Grow vertically up to the stratosphere. |
| White and fluffy. | Dark and heavy with rain. |
Q4: Answer the following
(a) Why is the air in a region dry?
Answer: Air is dry in regions with low moisture content due to high evaporation rates, less precipitation, and geographical factors like deserts or cold regions.
(b) How is humidity measured?
Answer: Humidity is measured using a hygrometer or psychrometer.
(c) What are the prerequisites for condensation?
Answer: High relative humidity, presence of dust particles, and cooling of air below the dew point.
(d) What is a cloud? Write its types.
Answer: A cloud is a visible mass of condensed water vapor or ice crystals in the atmosphere.
Types of clouds:
- High clouds: Cirrus, Cirrostratus, Cirrocumulus
- Medium clouds: Altocumulus, Altostratus
Low clouds: Stratus, Stratocumulus, Nimbostratus
Vertical clouds: Cumulus, Cumulonimbus
(e) Which type of clouds give rain?
Answer: Nimbostratus (continuous rain) and Cumulonimbus (stormy rain).
(f) On what does the percentage of relative humidity depend?
Answer: It depends on the absolute humidity and air temperature.
Q5: Give Geographical Reasons
(a) Clouds float in the sky.
Answer: Clouds are made of tiny water droplets or ice crystals, which are light and carried by air currents.
(b) The proportion of relative humidity changes according to altitude.
Answer: As altitude increases, temperature decreases, reducing the vapour-holding capacity of air, which affects relative humidity.
(c) Air becomes saturated.
Answer: Air becomes saturated when it reaches its maximum moisture-holding capacity at a given temperature.
(d) Cumulus clouds change into cumulonimbus clouds.
Answer: Due to strong vertical air currents, cumulus clouds grow larger, forming cumulonimbus clouds, which bring thunderstorms and heavy rain.
Q6: Solve the following
(a) When the temperature of the air is 30° C, its vapour-holding capacity is 30.37 gms/ cu.m. If absolute humidity is 18 gms / cu.m. then what would be the relative humidity?
Answer: (a) Relative Humidity Calculation
(b) What would be the absolute humidity of air if 1 cu.m. air contains 4.08 gms of vapour at 0°C temperature? .
Answer: (b) Absolute Humidity Calculation
- Given: 1 cu.m. air contains 4.08 gms of vapour at 0°C.
- Absolute Humidity = 4.08 g/m³.
Q 7. Collect the weather related information from newspapers for the month of July. Relate the difference in the maximum and minimum temperatures with humidity.
Answer:
- In July, the maximum and minimum temperatures vary due to cloud cover, monsoon conditions, and local weather patterns.
- High humidity levels during the monsoon season lead to increased chances of rainfall.
- Temperature fluctuations influence relative humidity, which is higher during cooler times of the day (morning and night) and lower during the afternoon.
- Coastal areas experience high humidity, while inland regions have moderate humidity levels.
Leave a Reply