Question

the area of a circle is given as s πr2. where r is radius of circle. find the change in area of circle as radius increased from 10cm to 10.001cm

Answer 1

Given :

Radius of the circle = 10 cm

Increase in the radius of the circle = 0.001 cm

To Find :

The increase in the area of the circle

Solution :

• The area of the circle is given by the formula A = πr²

• The increase in the area of the circle

                 $\Delta A= \frac{2\Delta r}{r}$

                 $\Delta A = 2\times\frac{0.001}{10}$

                 $\Delta A=0.0002$

                 $\Delta A = 0.02\%$

 The increase in the area of the circle is 0.02%