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Question
Is it true that the distance travelled by a circular wheel of diameter d cm in one revolution is 2 π d cm? Why?
Solution
Distance travelled by a circular wheel of radius r in one revolution equals the circumference of the circle.
We know that,
Circumference of the circle = 2πd; where d is the diameter of the circle.
Thus, it is not true that the distance travelled by a circular wheel of diameter d cm in one revolution is 2 d cm.
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