Skydiver Luke jumps with his parachute of diameter D = 12 m out of an airplane. The combined mass of the parachute and Luke is 100 kg. The drag coefficient for the fully open parachute is CD 1.4. Neglecting acceleration and considering a linear change of air density with altitude, estimate Luke's fall time between altitudes of 3000 m and 2000 m. For the density of air at these two altitudes, assume pair(3000m)= 1.0 kg/m³ and pair(2000m) 1.1 kg/m. %3D

Skydiver Luke jumps with his parachute of diameter D = 12 m out of an airplane. The combined mass of the parachute and Luke is 100 kg. The drag coefficient for the fully open parachute is CD 1.4. Neglecting acceleration and considering a linear change of air density with altitude, estimate Luke's fall time between altitudes of 3000 m and 2000 m. For the density of air at these two altitudes, assume pair(3000m)= 1.0 kg/m³ and pair(2000m) 1.1 kg/m. %3D

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.49P

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Skydiver Luke jumps with his parachute of diameter D = 12m out of an airplane. The combined mass of the parachute and Luke is 100 kg. The drag coefficient for the fully open parachute is C_{D} = 1.4 . Neglecting acceleration and considering a linear change of air density with altitude, estimate Luke's fall time between altitudes of 3000 m and 2000 m. For the density of air at these two altitudes, assume pair (3000m) = 1.0 kg/m³ and pair (2000m) = 1.1 kg/m³.
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