Question

Why do you think the rock is harder inside than outside?

Answer 1

• The gradual disintegration of rocks is caused by atmosphere forces. 
• The rocks when exposed to heat expand and contract when cooled down. 
• As surface rock contracts and expands and contracts again, it gradually becomes brittle and begins to break down.
• Water reacts with the chemicals in the rock and further weakens it. 
• These processes by which the rocks are weakened and broken are called ‘weathering’. 
• It is easier to chip small pieces of rock from the outer layer rather than from the core of the rock. 
• Thus we can say the rocks are harder inside than outside.