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Sladkaya [172]
2 years ago
7

A cross-country skier can complete a 7. 5 km race in 45 min. What is the skier’s average speed? km/h.

Physics
1 answer:
never [62]2 years ago
8 0

The average speed is a scalar quantity. The average speed of the skier is 10 km/hrs.

<h3>What is the average speed?</h3>

It is calculated by dividing the total distance by the total time elapsed.

The

\overline{v}={\frac{\Delta x}{\Delta t}}

Where,

\overline{v} = average velocity

{\Delta x} = displacement = 7.5 km

{\Delta t} = change in time = 45  min = 0.75 hours

Put the values in the formula,

\overline{v}={\frac{7.5 }{0.75 }}\\\\\overline{v}= 10 \rm \ km/hrs

Therefore, the average speed of the skier is 10 km/hrs.

Learn more about average speed:

https://brainly.in/question/32459982

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A) 12.57 m

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The formula that gives the relationship between the arc length or distance covered during circular motion to the angle subtended or the revolutions, is given as follows:

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where,

s = distance covered = ?

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Therefore,

s = (2 m)(2π radians)

<u>s = 12.57 m</u>

B) Angular Speed:

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ω = θ/t

where,

ω = angular speed = ?

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The formula that gives the the linear speed of an object moving in a circular path is given as:

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v = (2 m)(1.571 rad/s)

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