Question

(b) Give reason
(i) Mountaineers may suffer from nose bleeding at high altitudes.
(ii) It is much easier to cut fruits and vegetables with a sharp knife than a blunt knife.
(ii) Porters place a large round piece of cloth on their heads when they carry heavy loads.​

Answer 1

Answer:

1Mountain climbers often get nosebleeds at high altitudes because as the amount of oxygen in the air decreases and the air becomes drier, blood vessels inside your nose can crack and bleed.

Explanation:

2The pressure exerted by the sharp knife edge is more than that exerted by the blunt one because the area on which force is exerted with a sharp knife is very small. Thus, it is easier to cut with the former than with the latter.

3porters place a round piece of cloth on their head when they carry heavy lods as the round piece of cloth increases the area on which the load is placed. We know that when surface is more than pressure is less. As a result, the pressure on their heads get reduced.

Answer 2

Explanation:

I) Because as the amount of oxygen in the air decreases and air becomes drier, blood inside their nose can crack or bleed

ii) when we cut fruits with sharp knife then the area occupied by the knife to cut the fruit is and so the pressure exerted is more

ii) The round piece of cloth on their head increases the are on which the force will act