Give two examples each, of modes of transport used on land, water and air.

Two examples of modes of transport used on land are buses and wheel carts.

Two examples of modes of transport used on water are ships and boats.

Two examples of modes of transport used in air are aeroplanes and helicopters.

(i) One metre is __100__ cm.

(ii) Five kilometres is __5000__ m.

1 km = 1000 m

5 km = 1000 × 5 = 5000 m

Hence, the answer is 5000 m.

(iii) Motion of a child on a swing is __periodic__.

Periodic motion:

The motion of a swing repeats itself at a certain time interval. Therefore, it has periodic motion. Hence, a child on a swing is said to have periodic motion.

(iv) Motion of the needle of a sewing machine is __periodic__.

Periodic motion:

The needle of a sewing machine moves up and down repeatedly with a certain time interval. Hence, it is an example of periodic motion.

(v) Motion of the wheel of a bicycle is __circular__.

Circular motion:

The central part of the wheel of a bicycle is attached to a fixed point. The wheel rotates about this fixed point as the bicycle moves. Hence, the wheel has circular motion.