- #1
synergix
- 178
- 0
Homework Statement
a) if A is the area of circle with radius r and the circle expands as time passes, find dV/dt in terms of dr/dt
b)Suppose oil spills from a ruptured ranker 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?
Homework Equations
A=(pi)r2
The Attempt at a Solution
dA/dt= ((pi)r2)'=(r2+2(pi)r)
dA/dt= ((pi)2(30) + 302)
is this correct? it seems like an awfully big number what have I done wrong?