Question 1
- What is the solar system
- Briefly explain the forces that influence the shape of the earth
Answer
- The solar system is a group of heavenly bodies comprising the sun and the planets.
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- The shape of the earth is described as an oblate sphere/good
- The centripetal force pulls the poles towards each other causing flattening at the poles.
- The centrifugal force acts at the equator causing bulging. Gravitational force pulls everything on planet earth towards the centre
Question 2
- Distinguish between absolute humidity and relative humidity.
- State two factors that influence humidity
- Give two reasons why moisture in the atmosphere is significant
Answer
- Absolute humidity is the actual amount of water vapour/moisture in a given mass if air at a particular temperature whereas Relative humidity os the ration between th actual amount of water vapour in a given mass of air at a particular temperature to the maximum amount of water vapour it can hold at the same temperature
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1. Temperature
- Relative humidity reduces with rise in temperature if the moisture is kept constant. Because air expands and distribution of moisture per unit area reduces.
2. Supply of moisture
- If supply of moisture increases, the amount of moisture in the atmosphere rises. -
- Amount of moisture present in the atmosphere is an indication of the atmosphere’s
potential capacity to hold moisture and amount of precipitation an are an receive
- The amount of water vapour determines amount of energy stored in the atmosphere for the development of storms.
- Water vapour absorbs radiation regulating heat loss from the earth
Question 3
- Differentiate between weathering and mass wasting
- State two types of mechanical weathering
Answer
- Weathering refers to the physical/mechanical break down or chemical decay/decomposition of rock insitu (without movement) while mass wasting refers to the movement of weathered materials down the slope under the influence of gravity.
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- block disintegration
- granular disintegration
Question 4
- Differentiate between intensity and magnitude of an earthquake.
- State three human causes of earthquakes.
Answer
- The intensity of earthquake is how hard or strong the earthquake shakes the ground while magnitude is the amount of energy given off or produced during an earthquake
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Nucleus tests that cause explosions which trigger vibrations.
Moving trains on their rails which cause tremors
Load exerted by water in human made lakes can reactivate faulting thus causing tremors
Question 5
- Name two temperate grasslands.
- Give three uses of Savanna grasslands
Answer
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- Veldt of south Africa
- Pampas of Argentina -
- The grass provides pasture for grazing for livestock
- The grass increases humus in the soil making it suitable for cereal farming
- The vegetation act as soil cover this reducing soil erosion