I am a homeschooling mother. My daughter is in ABEKA
algebra and we are faced with a question I am not sure how to
answer. The problem is as follows: "Find to the nearest foot the
distance a body will fall in 5 1/5 seconds."
Now, we understand that the formula for such a problem is s = 1/2gt^2.
However, the solutions manual has the formula filled in as follows:
s= 1/2(32)(5.2). Where did the 32 come from? This was not explained
anywhere in the solutions manual or the teachers guide. Is 32 the standard
measure of gravity?
I like that you question what is going on rather than blindly accepting the
The acceleration due to gravity near the surface of the earth is -32
ft/sec/sec. In the metric system, the value is -9.8 meters/sec/sec.
This is due to the gravitational field intensity near the surface of the
earth. If we were to go to the moon, the value would be -1.6 m/s/s. It is
a local number, not a universal one.
Thanks for using NEWTON BBS!
---Nathan A. Unterman
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Update: June 2012