A spherical iron ball 8cm in diameter is coated with a layer of ice of uniform thickness. If the ice melts at the rate of 10cm^3/s ,how fast is the thickness of the ice decreasing when the coat of ice is 2 cm thick?

Question

zepdrix · Answer

Hmm I'm having a little trouble deciding which formula we're suppose to start with. The rest of the problem seems straight forward, but I can't seem to get what Thickness is referring to. Is that like.. the outer volume of the sphere? Or the change in the radius maybe?

anonymous · Answer

i think we could use this formula

anonymous · Answer

V=4/3π(r1)^3 -4/3π(r2)^3

anonymous · Answer

I think :( i'm not sure

zepdrix · Answer

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Does this work maybe? :O
Look at the picture, see what I did there?
Hmmmm maybe? :3

BTW, do you have an answer key that we can check our answer against?