Q5 of 78 Page 13

The radius of a circle is increasing at the rate of 0.5 cm/sec. Find the rate of increase of its circumference.

The circumference of a circle, with radius r, is defined as

C(r)=2πr – (1)


Given that , we have to calculate


Differentiating (1) with respect to t, we get





More from this chapter

All 78 →
3

The sides of an equilateral triangle are increasing at the rate of2 cm/sec. How far is the area increasing when the side is 10 cms?

 4

The side of a square is increasing at the rate of 0.1 cm/sec. Find the rate of increase of its perimeter.

 6

The side of an equilateral triangle is increasing at the rate of .... cm/sec. Find the rate of increase of its perimeter.

 7

Find the surface area of a sphere when its volume is changing at the same rate as its radius.