Question

If a snowball melts so that its surface area decreases at a rate of 0.2cm^2/min, find the rate at which the diameter decreases when the diameter is 13cm

Answer 1

Whats the equation for the surface area of a sphere?

Answer 2

Sa = 4*pi*r^2

Answer 3

Sa = 4*pi*(d/2)^2 = pi*d^2

Answer 4

dSa/dt = 2pi*d*(dd/dt)
0.2 = 2pi*13*(dd/dt)

Answer 5

dd/dt = 0.2/(26pi)

Answer 6

sorry jinnie i gotta go, got a class early in the morning tomorrow

Answer 7

thanks bahrom, take care