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**Hannibal lecter****Member**- Registered: 2016-02-11
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Hi,

write formula representing the function which it the volume of a sphere is proportional to the cube of its radius, r. ?

I found the answer if V= kr^3 which is V = 3/4*pi*r^3

how is that be??

before I look to the answer I solve it in my papers and wrote ( V= r^3 )

but I didn't wrote the 3/4*pi*!!

from where the solver bring this values ...

Wisdom is a tree which grows in the heart and fruits on the tongue

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**Hannibal lecter****Member**- Registered: 2016-02-11
- Posts: 225
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The average velocity, v, for a trip over a ﬁxed distance, d, is inversely proportional to the time of travel, t.

which is v= d/t

there is no a constant of proportionality here why?

with compare to other questions like that ( The number of animal species, N, of a certain body length, l, is inversely proportional to the square of l. )

which it N =k/l^2

now there is a constant again!

I got confused, when we put that " k " and when not?

Wisdom is a tree which grows in the heart and fruits on the tongue

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Hannibal lecter wrote:

There is: it's , the The average velocity, v, for a trip over a ﬁxed distance, d, is inversely proportional to the time of travel, t.

which is v= d/t

there is no a constant of proportionality here why?

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