Question

# A car runs at a constant speed on a circular track of radius $100m$, taking $62.8seconds$ for every circular lap. The average velocity and average speed for each circular lap respectively is:

A

$0,0$

No worries! We‘ve got your back. Try BYJU‘S free classes today!
B

$0,10m/s$

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C

$10m/s,10m/s$

No worries! We‘ve got your back. Try BYJU‘S free classes today!
D

$10m/s,0$

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is B $0,10m/s$Step 1: GivenRadius of the track, $r=100m$Time, $t=62.8seconds$Step 2: Formula used$Averagevelocity=\frac{Displacement}{time}$$Averagespeed=\frac{Dis\mathrm{tan}cecovered}{time}$Step 3: Determine the average velocity As the track is circular, the total displacement will be zero.Displacement is the shortest distance covered. And in the case of a circular path, the initial and final points coincide. Hence, the shortest distance will be zero.$Averagevelocity=\frac{Displacement}{time}\phantom{\rule{0ex}{0ex}}=\frac{0}{62.8}\phantom{\rule{0ex}{0ex}}=0$Step 4: Determine the average speedThe distance covered will be the circumference of the track.$Averagespeed=\frac{Trackcircumference}{time}\phantom{\rule{0ex}{0ex}}=\frac{2\mathrm{\pi r}}{t}\phantom{\rule{0ex}{0ex}}=\frac{2×3.14×100}{62.8}\phantom{\rule{0ex}{0ex}}=10m/s$Hence, option B is the correct option.

Suggest Corrections
10
Related Videos
Time, Average Speed and Velocity
PHYSICS
Watch in App
Explore more