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How Fast Does the Man Fall?

Date: 5/22/96 at 12:13:31
From: Anonymous
Subject: How many km per hour?

If a 180 lb. man drops 1150 feet from a building, how many km per hour 
will he be going when he hits the ground?

Date: 6/13/96 at 21:45:40
From: Doctor Paul
Subject: Re: How many km per hour?

In these physics problems, the weight of the man is unimportant.  The 
problem can be solved without knowing his weight.  The formula used 

    2        2
(vf)  =  (v0)   +  2*a*(delta y)


vf is the velocity of the object when it hits the ground 
     (or final velocity)
vo is the object's original velocity
a is the acceleration due to gravity
delta y is how far it falls

  2       2
vf  =  (0)  + 2*(32 ft/sec^2)*(1150 ft)

vf  =   73600 ft^2 / sec^2

now take the square root of vf^2 to get vf...

vf = 271.29 ft/sec                

-Doctor Paul,  The Math Forum
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Associated Topics:
High School Physics/Chemistry

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