Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Applications of Derivatives

Question:

Find the rate of change of the area of a circle per second when the radius increases at a speed of 2 cm/s and diameter D = 10 cm.

Options:

\[10\pi \]

\[4\pi \]

\[20\pi \]

\[8\pi \]

Correct Answer:

\[20\pi \]

Explanation:

dA/dt = \[4r\pi \]