(a) If A is the area of a circle with radius r and the circle expands as time passes, find dA/dt in terms of dr/dt.
(b) Suppose oil spills from a ruptured tanker and spreads in a circular pattern. If the radius of the oil spill increases at a constant rate of 1 m/s, how fast is the area of the spill increasing when the radius is 30 m?© BrainMass Inc. brainmass.com December 24, 2021, 5:04 pm ad1c9bdddf
A=Pi*r^2 indicates the area.
Now, to find what we want it suffices to ...
This shows how to find rate of change of area of an oil spill.