Question

A carriage wheel makes 1500 revolutions in going over a distance of 4.5 km. Find its radius.

Answer 1

Given distance covered by carriage wheel is $4.5km=4500m$
[Since, $1km=1000m$]
Since, Circumference $=2\pi r$
Thus, the distance = number of revolutions $\times$ circumference
$\Rightarrow 4500m=1500\left(2\pi r\right)$
$3000\left(3.14\right)r=4500$
$r=\frac{4500}{\left[\right(3000\left)\right(3.14\left)\right]}$
$r=0.47771m$
$\therefore r=0.47771\times 100cm=47.771cm$