Question

The bodies of fast moving vehicles are streamlined so that 

(1) they look nice 

(2) friction due to air or water decreases 

(3) they can not cut through air or water

(4) none of these

Answer 1

Correct option is (2) friction due to air or water decreases 

1. The streamlined shape offers a minimum force of friction in air or water, it helps to move faster.
2. Fast-moving vehicles are given a streamlined shape as their streamlined shape cuts through the air very easily and thus increased their speed.
3. The streamlined shape is given to aeroplanes in the air and ships in the water to reduce fluid friction.