What are called igneous rocks?
When the molten magma cools, it becomes solid. Rocks formed in this way are called igneous rocks.
Give reasons:
(i) We cannot go to the centre of the earth.
(ii) Sedimentary rocks are formed from sediments.
(iii) Limestone is changed into marble.
Answer the following questions briefly.
(i) What are the three layers of the earth?
(ii) What is a rock?
(iii) Name three types of rocks.
(iv) How are extrusive and intrusive rocks formed?
(v) What do you mean by a rock cycle?
(vi) What are the uses of rocks?
(vii) What are metamorphic rocks?