Question

Give reasons for the following: (a) The bodies of birds are streamlined.

(b) When we strike a matchstick against the rough surface, it catches fire.

(C) Grooves are made in tyres.

(d) A lubricant reduces friction.​

Answer 1

Explanation:

a)to reduce air resistance

B) due to high friction heat is generated thus fire is generated

C)to increase friction

d)as makes the surface smooth and less number of impurities