Question

A cyclist moving in a circular path of diameter 42 m completes three rounds of the
circular path in 60 seconds. Calculate the speed of the cyclist.

Answer 1

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ANSWER:

• The speed of the cyclist = 6.6 m/s

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GIVEN:

• diameter = 42 m

• Completes three rounds in 60 s

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TO FIND:

• The speed of the cyclist.

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EXPLANATION:

Radius = d/2 = 21 m

Distance travelled = 3 × perimeter of circle

Perimeter of circle = 2πr

Distance travelled = 3 × 2 × 22/7 × 21

Distance travelled = 6 × 22 × 3

Distance travelled = 18 × 22

Distance travelled = 396 m

Speed = Distance / Time

Time = 60 s

speed = 396 / 60

speed = 66 / 10

Hence the speed of the cyclist = 6.6 m/s

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Answer 2

Answer:

Explanation:

Solution,

Here, we have

Diameter = 42 m

Radius = d/2 = 42/2 = 21 m

Time taken in completing three rounds = 60 seconds

To Find,

Speed of cyclist,

We know that,

Circumference of a circle = 2πr

Distance covered = 3 × 2πr (For three circles)

⇒ Distance covered = 3 × 2 × 22/2 × 21

⇒ Distance covered = 3 × 2 × 22 × 3

⇒ Distance covered = 396 m.

Here, the distance covered is 396 m.

Now, the speed of the cyclist,

We know that,

Speed = Distance/Time

⇒ Speed = 396/60

⇒ Speed = 6.6 m/s.

Hence, the speed of the cyclist is 6.6 m/s.