Question

A cyclist moving on a circular track of radius $40m$ completes half revolution in $40s$. Its average velocity is:

• A. zero
• B. $4\pi$ m $s^{-1}$
• C. $2$ m $s^{-1}$
• D. $8\pi$ m $s^{-1}$

Answer 1

The correct option is (C) $2$ m $s^{-1}$

Step 1, Given data

The radius of the track = 40 m

Time = 40 sec

Step 2, Finding the average velocity

In half revolution:

Displacement $s$:

$s=$ diameter of circular track

$\Rightarrow s=80m$

$\left|averagevelocity\right|=\frac{\left|Dispalcement\right|}{timetaken}$

$V_{avg}=\frac{80}{40}$

$\Rightarrow V_{avg}=2m{s}^{-1}$

Hence the average velocity is 2 m/s