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3 years ago

What is the sprinters output at 2.0 s, 4.0 s and 6.0 s?

Physics

1 answer:

kari74 [83]3 years ago

5 0

A 59 kg sprinter, starting from rest, runs 47 m in 7.0 s at constant acceleration.?

What is the sprinter's power output at 2.0 s, 4.0 s, and 6.0 s?

Instantaneous Power is the force times velocity

P = Fv

Because the acceleration is constant, the force will be constant as well

F = ma

P = mav

for constant acceleration, the velocity at each time is found using

v = at

P = ma(at) = ma²t

find the acceleration using kinematic equation

s = ½at²

a = 2s/t²

a = 2(47) / 7.0²

a = 1.918 m/s²

P(2.0) = 59(1.918²)2.0 = 434.25 W = 0.43 kW

P(4.0) = 59(1.918²)4.0 = 868.51 W = 0.87 kW

P(6.0) = 59(1.918²)6.0 = 1302.76 W = 1.3 kW

I hope this helped.

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Answer:

$F = 1.5 \times 10^{-16} N$

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Explanation:

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