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The radius of a circular wheel is 42 cm. Find the distance travelled by it in :

(i) 1 revolution ;

(ii) 50 revolutions ;

(iii) 200 revolutions ;

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#### Solution

(i)

Radius of wheel, r = 42 cm

Circumference i.e. distance travelled in 1 revolution = 2πr = 2 x 22/7 x 42 = 264 cm

(ii)

Distance travelled in 50 revolutions = 264 x 50 = 13200 cm = 132 m

(iii)

Distance travelled in 200 revolutions = 264 x 200 = 52800 cm = 528 m

Hence (i) 264 cm (ii) 132 m (iii) 528 m

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