Thread: Cylinders

Water bubbles up at a rate of 1 cm^3/s, forimging a circular pond of depth 0.5 cm in his yard. How quickly is the surface area of the pond covering his lawn?


how would i find r to plug into the volume equation?

Originally Posted by Tascja

Water bubbles up at a rate of 1 cm^3/s, forimging a circular pond of depth 0.5 cm in his yard. How quickly is the surface area of the pond covering his lawn?


how would i find r to plug into the volume equation?

The volume of the pond is:



where is the depth of the water, and is the surface area of the pond.

So the rate of change of volume is:



but we are told that this is , and as we have:



RonL