HELP WITH MATH IM CRYING?
a stone dropped into a pond causes a circular ripple to move outwards the radius of the ripple increasing at the rate of 2m/sec. How fast is the area inside the ripple changing when the radius is 5 meters?
a stone dropped into a pond causes a circular ripple to move outwards the radius of the ripple increasing at the rate of 2m/sec. How fast is the area inside the ripple changing when the radius is 5 meters?
Wayne DeguMan
dr/dt = 2
Area is πr²
so, dA/dt = 2πr.dr/dt
or, dA/dt = 2πr(2) => 4πr
With r = 5, we have dA/dt = 20π => 62.83 m²/sec
:)>
alex
A = πr^2 , given dr/dt = 2 m/s at r=5
dA/dt = 2πr(dr/dt)=2π(5)(2)=20π m^2/s