Question

How long will a man take to make a round of a circular field of radius 21 m, cycling at the
speed of 8 km/hr?​

Answer 1

Answer:

$\large\bold\red{0.0165\;hr}$

Step-by-step explanation:

Given ,

A circular field,

• Radius, r = 21 m

Therefore,

We get,

• Circumference ,c = 2πr

$= > c = 2 \times \frac{22}{7} \times 21 \\ \\ = > c = 2 \times 22 \times 3 \\ \\ = > c = 22 \times 6 \\ \\ = > c = 132 \: m$

Now,

It's the distance which has to be covered.

Therefore,

We get,

• Distance, d = 132 m

Or,

• $d = 132 \times {10}^{-3}\; Km$

Now,

It's given,

• Speed, v = 8 Km/hr

Now,

Let the time taken is t.

But,

We know that,

• $distance = speed \times time$

Therefore,

We get,

$= > d = v \times t \\ \\ = > t = \frac{d}{v}$

Substituting the values,

We get,

$= > t = \frac{132 \times {10}^{ - 3} }{8} \\ \\ = > t = \frac{33}{2} \times {10}^{ - 3} \\ \\ = > t = 16.5 \times {10}^{ - 3} \\ \\ = > t = 0.0165 \: \: hr$

Hence,

Te man will take 0.0165 hours to make a round of the circular field.