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 ; - Mathematics

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Sum

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

Concept: Area of Circle
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Chapter 20: Area of a Trapezium and a Polygon - Exercise 20 (D) [Page 235]

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Selina Concise Mathematics Class 8 ICSE
Chapter 20 Area of a Trapezium and a Polygon
Exercise 20 (D) | Q 12 | Page 235

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