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Question
A bicycle wheel makes 500 revolutions in moving 1 km. Find the diameter of the wheel.
Solution
A bicycle wheel makes 500 revolutions in moving 1 km.
In 1 revolution, the bicycle wheel covers = `1/500` km
= `1000/500` m ...[∵ 1 km = 1000 m]
= 2 m
In 1 revolution distance = Circumference/Perimeter of the wheel
⇒ 2πr = 2
⇒ `2 xx 22/7 xx r = 2`
⇒ `r = (2 xx 7)/(2 xx 22) = 7/22` ...[∵ Circumference of a circle = 2πr]
∴ Diameter (d) = 2r
= `7/22 xx 2`
= `7/11`
= 0.636 m
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