An athlete completes one round of a circular track of diameter 14m with a uniform speed of 11m/s. Find the time taken.

Step 1: Given data :

1. Diameter= 14 m
2. So Radius = r = 7m
3. Uniform speed = 11m/s

Step 2:Finding time:

We know that,

$Speed=\frac{Dis\tan ce}{Time}$ and $Time=\frac{Dis\tan ce}{Speed}$

Distance covered in one round = Circumference of a circle = 2πr where r is the radius of the circular path and $\mathrm{\pi }=3.14$.

$$\begin{gathered} =2\times 7\times \pi \\ =14\pi m \end{gathered}$$

Finding time taken by an athlete:

$Time=\frac{Dis\tan ce}{Speed}$

$=\frac{14\mathrm{\pi }}{11}=\frac{14\times 3.14}{11}=3.99\approx 4sec.$

Therefore, the time taken by an athlete is 4 seconds.