CBSE Class 6 Science Our Earth Assignment Set 03

OUR EARTH

Question. Name the three layers of the earth?
Answer: Crust-upper layer, Mantle-middle layer and Core-innermost layer.

Different layers of the Earth

Question. How thick is earth crust?
Answer: The thickness of the earth curst varies from 35 to 60 km.

Question. In which layer of the earth are minerals found?
Answer: Most of the minerals are found deep inside the upper layer of the earth called curst.

Question. Why can't we notice earth's motion?
Answer: We don't notice because everything around us is moving along with the earth.

Question. What is the contribution of Aryabhatta to astronomy?
Answer: He was one of the greatest scientist of ancient India. Most of his work is related to astronomy. He carried out research on the motion of heavenly bodies. He also calculated the value of pi(\(\pi\)). He discovered that day and night are due to the rotation of the earth.

The first Indian Satellite-Aryabhata

Question. What do you find common in all living organisms?
Answer: Each one of them needs food, grows, reproduces and ultimately dies.

Question. Why is earth spherical in shape inspite of so many ups downs on its surface?
Answer: This so because the earth is very large. The ups and downs on its surface are very small in comparison with its size.

Question. What are the approximate temperature and pressure at the centre of the earth?
Answer: Temperature is \(4000^\circ\text{C}\) and 3.7 million times atmospheric pressure.

Question. What about the inside of the earth?
Answer: The inside of the earth is solid. The upper layer forms the crust, the middle layer forms the mantle and the innermost region is core, which is believed to exist in solid form or solid in molten slate.

Question. What do we find inside the core ?
Answer: Core is the hottest and the innermost region of the earth. It consists of mainly iron.