Question

An athelete completes 1rpund of a circular track of dieyer 200m in 40seconds. What will be the distance covered and the displacement at the end of 2minutes 20 seconds

Answer 1

$\underline{\mathfrak{\huge{Answer:}}}$

$\sf{Given\:is\:that:}$

Diameter of the circulate track = 200 m

Time taken to complete 1 round = 40 s

$\sf{To\:Find:}$

The distance and the displacement after 2 minutes 20 seconds

$\sf{Your\:Solution:}$

Circumference of the track = $2 \pi r$

Radius = $\frac{D}{2}$

=》 Radius = $\frac{200}{2}$

=》 Radius = 100 m

=》 Circumference = 200π 

Put the value of π 

=》 $\frac{4400}{7}$

Speed = $\frac{D}{T}$

Speed = $\frac{4400}{7}\times\frac{1}{40}$

Speed = $\frac{110}{7}$

Distance covered in 140 seconds ( 2 minutes 20 seconds = 120 + 20 seconds ) = Speed × Time

=》 $\frac{4400}{7}\times 140$

Distance =》 $\boxed{\tt{2200 m}}$

Number of rounds in 2200 m = $2200 \times \frac{7}{4400}$

=》 $\tt{3.5 rounds}$

Displacement after 3.5 rounds = 200m

Displacement after 2 minutes 20 seconds = $\boxed{\tt{200 m}}$

Answer 2

Hello!

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Given,

Diameter = 200m

Time = 40s ( 1 round )

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We have to now find distance of 2 minuted 20 second's (140 seconds )

We know that,

Radius = d/2

Therefore,

Radius = 200/2

Radius = 100 m

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We have now, Diameter, radius, cirmufernece.

Now,

22/7*200π

=> 4400/7

=> 4400/7*1/40

=> 110/7

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Distance = 4400/7*140sec

Distance = 2200m

According to question we have to find No of rounds.

That's why,

2200*7/4400

=> 3.5 rounds

Displacement => 200m