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applied circumference problem..finding distance?

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by moutar » Sun Apr 12, 2009 3:04 pm
The distance between the centre of the two wheels is the same as the horizontal part of the belt.

The part that is touching each wheel is equal to half the diameter for each one.

Answer = (Total length - 2 x half circumference)/2
= (15 - 2 x pi x 0.5)/2
= (15 - pi)/2 A.
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by coolgirl26 » Sun Apr 12, 2009 3:36 pm
why did u divide by 2

i get that the horizontal line is 15

and its touching 1/2 of the circumference of each circle

but i stil dont get how this is formed 15-pi/2

can u explain it in depth please

thank u
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by moutar » Sun Apr 12, 2009 3:44 pm
The whole belt is made up of 2 horizontal parts (top and bottom) and 2 round half-circumference parts.

So:

15 = Top + bottom + 2 x half circle

Top = bottom (call this A)

15 = 2A + 2 x pi*d/2 (d=1)
15 = 2A + pi

15 - pi = 2A

A = (15 - pi)/2
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by coolgirl26 » Sun Apr 12, 2009 3:48 pm
ohhhhhh okay thankkkk youuuu
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