Manipur Board Class 7 Social Science Chapter 2 Natural Environment Land Question Answer Solution. We have uploaded this page so that students of Manipur State Board can learn online by their smartphone / laptop or other devices.
Manipur Board Class 7 Social Science Chapter 2: Natural Environment Land
- Board – Board of Secondary Education, Manipur.
- Class – 7
- Subject – Social Science
- Topic – Exercise Solution / Notes / Question Answer.
1.) Answer the questions in a word or a sentence :
(a) Name the layer of the earth in which S waves can not pass through.
Ans- The layer of the earth in which S waves can not pass through is the CORE of the Earth.
(b) What type of rock is formed when lava solidifies on the surface of the earth ?
Ans- Igneous rocks are formed when molten rock called magma cools and solidifies.
(c) Which force is responsible for the folding of rock strata ?
Ans – The compressional forces lead to the bending of rock layers or folding of rock strata.
2.) Answer the following questions in about 40 words each :
(a) How are metamorphic rocks formed ? Give two examples.
Ans- Igneous as well as sedimentary rocks undergo changes. The process of change is called metamorphism. When the original character of the rocks, i.e.colour, hardness and mineral composition is changed due to heat and pressure, it gives rise to metamorphic rocks.
Eg – Granite (igneous) changes into gneiss and sandstone (sedimentary) changes into quartzite.
(b) What is a rock cycle ?
Ans- This process of transformation of the rock from one to another is known as the rock cycle. Rocks are changed into another type under different conditions. Igneous rock is exposed to weathering and erosion, and changed into sedimentary rocks.
(c) What do you understand by Endogenic forces ?
Ans- The forces which originate inside the earth and bring changes on the surface are known as Endogenic or Internal forces.
(d) Differentiate between vertical and horizontal movements of the earth.
Ans- The differences between vertical and horizontal movements of earth are as follows:
i) Vertical movements are responsible for a rise or a fall of a part of the earth’s surface whereas Horizontal earth movements disturb the horizontal arrangement of rock layers.
ii)Vertical movements build up continents whereas horizontal movements are responsible for the formation of mountains and are, therefore, known as mountain-building movements.
3.) Choose the correct answer :
(i) Rift valleys are formed between two –(a) Fold Mountains
(ii) The plateau which is enclosed by mountains is called-(d) Intermontane Plateaus.
(iii) The Imphal valley is a lacustrine plain because it was formed due to – (c) sedimentation in a lake.
4.) Give the correct term for the following :
(a) The place of origin of an earthquake inside the earth – Core
(b) The molten part of the upper mantle- Crust
(c) Remains of plants and animals found in sedimentary rocks – Fossils fuels.
(d) The fracture in rocks involving movement of strata- Faulting.
(e) The upfolds of rock strata – Anticlines