MCQ
A wheel completes $2000$ revolutions to cover the $9.5\, km$. distance. then the diameter of the wheel is
- ✓$1.5\, m$
- B$1.5 \,cm$
- C$7.5 \,cm$
- D$7.5 \,m$
✓
Answer
Correct option: A.
$1.5\, m$
a
(a) Distance covered in ‘$n$’ revolution $= n 2\pi r= n\pi \,D$
(a) Distance covered in ‘$n$’ revolution $= n 2\pi r= n\pi \,D$
$ \Rightarrow 2000\,\pi \,D = 9500$ [As $n = 2000$, distance $= 9500\, m$]
$⇒$ $D = \frac{{9500}}{{2000 \times \pi }} = 1.5\,m$
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