# What is the radius of the circular plate of thickness 1 cm made by melting a sphere of radius 3 cm ?

What is the radius of the circular plate of thickness 1 cm made by melting a sphere of radius 3 cm ?

A. 6 cm

B. 5 cm

C. 4 cm

D. 7 cm

**Answer : **A. 6 cm

## Explanation :

Given that radius of sphere r = 3 cm

Given that thickness of the plate h = 1 cm

Given that a sphere is melt to produce a circular plate.

Since nothing is added or subtraced then volume of sphere and circular plate both will be equal.

Volume of sphere

Volume of circular plate

set both volumes equal to each other

36 = r^{2}

6 = r

Hence the radius is **6 cm.**