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2 years ago

7

A 72 kg skydiver can be modeled as a rectangular "box" with dimensions 21 cm × 41 cm × 170 cm . if he falls feet first, his drag

coefficient is 0.80. part a what is his terminal speed if he falls feet first? use ρ = 1.2 kg/m3 for the density of air at room temperature.

1 answer:

LuckyWell [14K]2 years ago

4 0

Formula for terminal velocity is:

Vt = √(2mg/ρACd)
<span>Vt = terminal velocity = ?
<span>m = mass of the falling object = 72 kg
<span>g = gravitational acceleration = 9.81 m/s^2
<span>Cd = drag coefficient = 0.80
<span>ρ = density of the fluid/gas = 1.2 kg/m^3</span>
<span>A = projected area of the object (feet first) = 0.21 m * 0.41 m = 0.0861 m^2

Therefore:</span></span></span></span></span>

Vt = √(2 * 72 * 9.81 / 1.2 * 0.0861 * 0.80)

<span>Vt = 130.73 m/s</span>

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