Question

what happens to the volume of a sphere when its radius is doubled?
a,Its volume is doubled
b,2r^3 cubic units are added to the volume
c,its volume is 2^3 times is original voume
d,none of the answer choices are true

Answer 1

vsphere=(4/3)pir^3

when we replace r with 2r

newvsphere=(4/3)pi(2r)^3
newvsphere=(4/3)pi8r^3
newvsphere=8((4/3)pir^3)
newvsphere=8(vsphere)
it's volume is multipliied by 8

that is choice C, because 2^3=8, it's vollume is 8 times original voluem


answer is C