Yahoo Answers: Answers and Comments for How fast would a golf ball fall if dropped from an airplane? In MPH. How long to reach that speed? [Physics]
Copyright © Yahoo! Inc. All rights reserved.
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
From Bill
enUS
Thu, 28 Nov 2019 23:22:07 +0000
3
Yahoo Answers: Answers and Comments for How fast would a golf ball fall if dropped from an airplane? In MPH. How long to reach that speed? [Physics]
292
38
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
https://s.yimg.com/zz/combo?images/emaillogous.png

From oubaas: Drag force F:
F = ρa*V^2/2*C*A
being :
C the ...
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
Fri, 29 Nov 2019 05:02:58 +0000
Drag force F:
F = ρa*V^2/2*C*A
being :
C the drag coeff (0.5 for a sphere)
A the crosssection area PI*r^2 in m^2
ρa the density of air equal to 1.25 kg/m^3
V the speed in m/sec
weight force WF = 4/3*PI*r^3*ρb*g (ρb is the density of ball equal to 1250 kg/m^3)
terminal speed is given when such quantities equate , i.e. :
ρa*V^2/2*C*PI*r^2 = 4/3*PI*r^3*ρb*g
since ρb/ρa = 1250/1.25 = 10^3 , g ≅ 10 m/sec^2 and r = 21.4*10^3 m, then :
V^2/4 = 4/3*21.4*10^3*10^3*10
V = √ 21.4*16/3*10 ≅ 34 m/sec = 76 MPH
the time needed for reaching that speed is nearly 3 times the time taken in vacuum , i.e. 3*34/10 ≅ 10 sec

From Morningfox: The ball will start at zero speed downwards, a...
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
Fri, 29 Nov 2019 00:55:29 +0000
The ball will start at zero speed downwards, and then ramp up to 72 mph (terminal velocity). It will take about 6.5 seconds to reach that speed. The sideways speed will start with whatever the airplane has, and in 7 to 10 seconds decrease to nearly zero.

From Aster Rhoids: Depends on the elevation
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
https://answers.yahoo.com/question/index?qid=20191128232207AAzFIVL
Thu, 28 Nov 2019 23:22:43 +0000
Depends on the elevation