Question

.A runner travels 1.5 laps around a circular track in a time of 50 seconds . The diameter of the track is 40 metre. Calculate the average velocity. Give The solution step by step ​

Answer 1

Answer:

0.8 m/s

Explanation:

As per the provided information in the given question we have,

• A runner travels 1.5 laps around a circular track in a time of 50 seconds.
• Diameter of the track = 40 m

We are asked to calculate the average velocity.

$\longmapsto \bf {Velocity_{(avg)} = \dfrac{Total \; displacement}{Total \; time} }$

In order to calculate the average velocity, we

firstly we need to calculate total displacement and the total time.

Total time is already given, that is 50 seconds.

Total displacement :

Suppose that the body starts from point A .We've to find its final position to calculate its displacement. The runner takes 1.5 laps, after 1 lap it'll come back again to point A. Then, it'll have to take half or 0.5 laps more in order to complete 1.5 laps.

So, after coming back again to point A after taking 1 lap and then covering half lap, it'll come to point B, which is its final position.

Total displacement is the shortest distance from initial position to final position. Here, shortest distance from A to B is AB which the diameter of the circular track.

⇒ Displacement = Diameter

⇒ Displacement = 40 m

Average Velocity :

$\longmapsto \rm {Velocity_{(avg)} = \dfrac{Total \; displacement}{Total \; time} }$

$\longmapsto \rm {Velocity_{(avg)} = \dfrac{40 \; m}{50 \; s} }$

$\longmapsto \rm {Velocity_{(avg)} =\cancel{ \dfrac{4 \; m}{5 \; s}} }$

$\longmapsto \bf {Velocity_{(avg)} = 0.8 \; ms^{-1} }$

∴ 0.8 m/s is the average velocity.