Calc help please!! 1) A spherical snowball is melting in such a way that its rad
ID: 2884594 • Letter: C
Question
Calc help please!!
1) A spherical snowball is melting in such a way that its radius is decreasing at rate of 0.1 cm/min. At what rate is the volume of the snowball decreasing when the radius is 8 cm. (Note the answer is a positive number).
2) A circle is inside a square. The radius of the circle is decreasing at a rate of 1 meter per day and the sides of the square are increasing at a rate of 5 meters per day. When the radius is 5 meters, and the sides are 21 meters, then how fast is the AREA outside the circle but inside the square changing?
The rate of change of the area enclosed between the circle and the square is _____ square meters per day.
Explanation / Answer
1. Volume = (4/3) pi r3
dV/dt = (4/3) pi r2(dr/dt)
dV/dt = 4 pi (8)2(-0.1) = -80.4 cm3/min
So the volume is decreasing at the rate of 80.4 cm3/min