Question

A stone is thrown in silent water, the ripples are moving at the rate of 6 cm0/sec. then the rate of change of the area when the radius of the unite is 10 cm. at the time when radius of the circle is 10 cm, then the rate at which its area increases is :

विकल्प

• 120 m² /sec 

• π cm² /sec

• 120 m² /sec 

• 120 π m² /sec 

Answer 1

120 π m² /sec