Question

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

Answer 1

The correct option is A 1.5 m

Number of revolutions copleted $=2000$ rev.
If the diameter of wheel is $d$ m.
Then the distance moved in on revolution $=\pi d$ m.
Distance moved in $2000$ revolution $=\pi d\times 2000$ m.
But total distance move$=9.5$ km (Given).
So,
$\pi d\times 2000=9.5\times 1000$
$d=\frac{9.5\times 1000}{\pi \times 2000}$
$d=1.51$ m $\approx 1.5$ m