A wheel completes 2000 revolutions to cover 9.5, km . distance. then diameter of wheel is

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3-2.Motion in Plane

easy

A wheel completes $2000$ revolutions to cover the $9.5\, km$. distance. then the diameter of the wheel is

A$1.5\, m$

B$1.5 \,cm$

C$7.5 \,cm$

D$7.5 \,m$

Solution

(a) Distance covered in ‘$n$’ revolution $= n 2\pi r= n\pi \,D$
$ \Rightarrow 2000\,\pi \,D = 9500$ [As $n = 2000$, distance $= 9500\, m$]
$⇒$ $D = \frac{{9500}}{{2000 \times \pi }} = 1.5\,m$

Standard 11

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