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Anonymous Poster

Rate of Change Shadow Problem

10/09/2008 12:24 AM

A light is placed 3 ft above the ground and 32ft. from the wall of a building. A man 6 ft tall walks from the light towards the building at rate 6 ft/ sec. Find the rate at w/c the height of shadow on the wall is decreasing when he is 8 ft. from the wall
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Anonymous Poster
#1

Re: Rate of Change Shadow Problem

10/09/2008 12:32 AM

What rate is the area of the base increasing when its radius is 15 ft.?
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JohnDG
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#2

Re: Rate of Change Shadow Problem

10/09/2008 3:33 AM

We've got enough homework of our own.

If you draw a diagram of the problem, and do a bit of simple geometry (or trig, if you must), it's not too hard to work it out for yourself.

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guacamojo
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#3

Re: Rate of Change Shadow Problem

10/09/2008 12:24 PM

1 ft/sec
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standarded
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#4

Re: Rate of Change Shadow Problem

10/09/2008 10:59 PM

Go get your introductory calculus book and see how it is done.

We don't do homework here.

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OldTechNewToys
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#5

Re: Rate of Change Shadow Problem

10/10/2008 1:48 AM

1.5ft/sec :)
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snygolfgs
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#6

Re: Rate of Change Shadow Problem

10/12/2008 1:35 PM

Like everybody said...work the problem out...

I got a little more than .75 ft./sec @ 8 ft. but rate will continue to decrease during the approx. 1.33 seconds it takes to reach the wall from 8 feet.

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