How is the volume of a cylinder affected when its radius is doubled?

1 Answer
Aug 3, 2016

Volume quadrupled.

Explanation:

V_("cylinder") = pir_("cylinder")^2h

therefore V prop r^2 implies V = kr^2

Let r_2 = 2r_1, then

V_2/V_1 = (kr_2^2)/(kr_1^2) = r_2^2/r_1^2

V_2 = V_1(r_2/r_1)^2 = V_1((2r_1)/(r_1))^2 = V_1(2)^2 = 4V_1