SPS
SPS FM Pure
2023
June
Q6
5 marks
Standard +0.3
A spherical balloon is inflated so that its volume increases at a rate of \(10\text{ cm}^3\) per second.
Find the rate of increase of the balloon's surface area when its diameter is 8 cm.
[For a sphere of radius \(r\), surface area \(= 4\pi r^2\) and volume \(= \frac{4}{3}\pi r^3\)]. [5]