Question

a man running around a circular track of radius 20 m covers one complete round in 40 s . calculate the distance and displacement covered by him in 3 minutes​

Answer 1

Answer:

radius of circular track = 20

so the circumference = 2$\pi$r

                                    =2×22×20/7

                                    =125.663m approx.

so it means he complete 125.663 in 40sec

so now round cover by him in 3 min or 180 sec.  

                                                           = 180/4×125.663

                                                           =5654.835 m.

                   

Explanation:

Answer 2

The distance covered is 565.2 meters and displacement covered is 62.8 meters

GIVEN

A man running around a circular track of radius 20 m covers one complete round in 40 s.

TO FIND

The distance and displacement covered by him in 3 minutes.

SOLUTION

We can simply solve the above problem as follows;

We know that distance is the measure of the path taken from initial to final direction and Displacement is the shortest distance between initial and final distance.

Now,

Radius of circular track = 20 m

Distance covered in 1 round = Circumference of the circular track

Circumference of the Circular track = 2πr

= 2× 3.14 × 20

= 125.6 meters

So,

The man has covered 125.6 meters in 40 seconds.

Now,

Number of rounds completed in 40 seconds = 1

Number of round completed in 3 minutes (180 seconds) = 180/40 = 4.5 rounds

Distance covered in 4.5 rounds = 125.6 × 4.5 = 565.2 meters.

Now, Displacement of the man in 4 complete turns will be zero (Since the initial and final points are same)

Displacement in 0.5 turn = Half of the circumference of the track.

= 125.6/3

= 62.8 meters

Hence, The distance covered is 565.2 meters and displacement covered is 62.8 meters

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