Question

Find the number of revolutions made by a circular wheel of area $1.54$ $m^2$ in rolling a distance of $176$ m.

• A. $400$
• B. $44$
• C. $40$
• D. $220$

Answer 1

Answer: (C)

$40$

Given-

A wheel has an area $A=1.54m^2$.

It covers a distance $d=176$ m.

To find the number of revolutions $\left(n\right)$ it makes to cover $d=?$

Solution-

The radius $r$ of the wheel$=\sqrt{\frac{A}{\pi }}=\sqrt{\frac{1.54\times 7}{22}}=0.7$ m

$\therefore$ The circumference$=C=2\pi r=2\times \frac{22}{7}\times 0.7=4.4$ m

So, $n=\frac{d}{C}=\frac{176}{4.4}=40$

So, number of revolutions made by a circular wheel are $40$.