ExamBro
ExamBro
COMEDK · Maths · 27. Application of Derivatives

If the volume of a sphere is increasing at a constant rate, then the rate at which its radius is increasing is

  1. A proportional to the radius
  2. B inversely proportional to its surface area
  3. C inversely proportional to the radius
  4. D a constant
Verified Solution

Answer & Solution

Correct Answer

(B) inversely proportional to its surface area

Step-by-step Solution

Detailed explanation

The volume \(V\) of a sphere of radius \(r\) is given by \(V = \dfrac{4}{3} \pi r^{3}\). Differentiating both sides with respect to time \(t\), we get \(\dfrac{dV}{dt} = 4 \pi r^{2} \dfrac{dr}{dt}\). It is given that the volume is increasing at a constant rate, so…