Question 1
- What is a line of longitude?
- State three effects of rotation of the earth
- Name four layers of the earth’s atmosphere
- Describe the composition of the crust
Answer
- It’s a line based on the angular displacement of a place east or west of the prime meridian 0 degrees
-
i. It causes the occurrence of days and nights / apparent movement of the sun from east to west
ii. Is leads to the rising and falling of the sea / ocean tides / high and low tides
iii. It causes differences in the time over the earth’s surface / time difference at different longitudes -
i. troposphere
ii. stratosphere
iii. mesosphere
iv. thermosphere - - made up of social rocks
- the sial is made up of lighter rocks 127gms/cc
- it is composed of two layers the sial / continental crust and sima / oceanic crust
- the sima is rich in silica and magnesium
- the sima is made up of dense rocks
Question 2
The diagram below shows the angle of the sun’s rays at different latitudes when the sun is at the equator. Use it to answer the questions (a) and (b)
- Name the parts of the earth surface J and K
- Give three reasons why the intensity of the insolation is higher at M than at N
- What is land breeze?
- Give four reasons why weather forecasting is important
Answer
-
J – North pole
K – South pole -
- There is higher concentration of heating at M than at N because the surface area at M is small than N
- The angle of sun’s rays at M is higher than at N hence the variation in intensity (right angle/ perpendicular at M )
- At N sun’s rays travel over a long distance than at M thus losing the heat resulting to low intensity - - It is a mass of cool air blowing from the land to the sea during the night
-
- It enables the farmer to plan their farming activities
- Help people to choose the clothing for the day
- It influences design of houses
- It guides in timing for sporting / tourist activities
Question 3
The table below shows the temperature and rainfall figures for a weather station in Kenya. Use it to answer questions that follow.
i) Draw a simple bar graph to represent the rainfall distribution show the table above
ii) Calculate mean annual temperature
iii) The annual range of temperature for the station- Apart from water vapor/ name three other substances that are suspended in the atmosphere
- Give three characteristics of sedimentary rocks
- Give two types of igneous rocks
-
Name two types of rocks which result from metamorphism of the following rocks
i) Granite
ii) Clay
Answer
i)
ii)
iii) 17.10C - 150C = 2.10C-
- Dust particles
- Pollen grains
- Gases -
- Some sedimentary rocks contain fossils / remains of plants and animals
- The rocks have cleavage / are foliated / have bending planes
- The rocks from horizontal layers / are stratified -
intrusive / plutonic rocks
extrusive / volcanic rocks -
Name two types of rocks which result from metamorphism of the following rocks
i) Granite - Gneiss
ii) Clay - Slate
Question 4
- Name two types of tectonic plate boundaries
- Describe the origin of the continents according to the theory of continental drift
- Differentiate between orogeny and orogenesis
- Name four major orogenies
Answer
-
1. Divergence / extension / constructive
2. Convergence / compressional / destruction -
- The earth was originally one huge land mass / pangeal super continent
- Pangea was surrounded by a large super water body / sea called pauthalassa
- Pangea split into two sub-continents to form two other land masses called Laurasia and Gondwanaland
- The two landmasses were separated by a sea called Tethys
- Further split occurred on the two land masses
- Laurusia broke to form the continent’s in the southern hemisphere
- The continent’s gradually drifted to their present position - Orogeny is the period of fold mountain formation while orogenesis is the process of fold mountain formation
-
- Charnian orogeny
- Caledonian orogeny
- Hereynian / armorican orogeny
- Alphine orogeny
Question 5
- What is a fault
- Briefly explain how the following forces / processes cause faulting
- Compressional forces
- Tensional forces
Answer
- It is a fracture or a cruck in the crust along which displacement of rocks occur
-
- Compressional forces – they are forces that act horizontally towards each other squeezing rocks and making them shorten, fold and fracture
- Tensional forces– this are forces that act horizontally and parallel to each other in opposite directions. They cause tearing of crystal rocks