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Novosadov [1.4K]

2 years ago

12

A runner runs around a circular track. He completes one lap at a time of t = 269 s at a constant speed of v = 4.6 m/s. What is t

he radius, r in meters, of the track?

1 answer:

AURORKA [14]2 years ago

5 0

Answer:

$\boxed{\text{197 m}}$

Step-by-step explanation:

The formula relating distance (d), speed (s), and time (t) is

d = st

1. Calculate the distance

d = 269 s × 4.6 m·s⁻¹ = 1240 m

2.Calculate the track radius

The distance travelled is the circumference of a circle

$\begin{array}{rcl}C & = & 2 \pi r\\1240 & = & 2 \pi r\\\\r & = & \dfrac{1240}{2 \pi }\\\\& = & 197\\\end{array}\\\text{The radius of the track is }\boxed{\textbf{197 m}}$

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Read more about parabola at:

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