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To: RansomOttawa

I have doubts concerning the physics behind this freefall. Could somebody explain to me the apparent breaking of the laws of physics going on here. Terminal velocity is 134 miles/hr. How is is possible to break the sound barrier. Notice the following.

Terminal Velocity Examples
Falling object Mass Area Terminal velocity
Skydiver 75 kg 0.7 m^2 60 m/s 134 mi/hr
Baseball (3.66cm radius) 145 gm 42 cm^2 33 m/s 74 mi/hr
Golf ball (2.1 cm radius) 46 gm 14 cm^2 32 m/s 72 mi/hr
Hail stone (0.5 cm radius) .48 gm .79 cm^2 14 m/s 31 mi/hr
Raindrop (0.2 cm radius) .034 gm .13 cm^2 9 m/s 20 mi/hr


Data from Serway, Physics for Scientists and Engineers, Table 6.1. A drag coefficient C=0.5 is assumed, falling through air.

Is it due to the drag coefficient being a great deal less at the high elevation? Makes you wonder.


39 posted on 12/14/2004 9:18:26 AM PST by Shobutao
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To: Shobutao

I believe your numbers are valid for STP.. But at 130k feet, air resistance is pretty much non-existant...


42 posted on 12/14/2004 9:23:49 AM PST by tje
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To: Shobutao

Simple, at the altitude he will be jumping from, the density of the atmosphere is minimal. The table you cite are for near sea level.

Check out Project Excelsior.

"On the third and last jump in Excelsior III on August 16, 1960, Captain Kittinger jumped from a height of 102,800 feet, almost 20 miles above the earth. With only the small stabilizing chute deployed, Kittinger fell for 4 minutes, 36 seconds. He experienced temperatures as low as minus 94 degrees Fahrenheit and a maximum speed of 714 miles per hour, exceeding the speed of sound."


43 posted on 12/14/2004 9:27:02 AM PST by Tijeras_Slim (I'm here because I'm not all there.)
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