Question

The diameter of a metallic ball is 4.2 cm. What is the mass of the ball, if the density of the metal is 8.9 g per cm³?

`["Assume "pi=22/7]`

 

Answer 1

Radius (r) of metallic ball = `(4.2/2)cm` = 2.1 cm

Volume of metallic ball = `4/3pir^3`

= `[4/3xx22/7xx(2.1)^3]cm^3`

= 38.808 cm³

Density = `"Mass"/"Volume"`

Mass = Density × Volume

= (8.9 × 38.808) g

= 345.3912 g

Hence, the mass of the ball is 345.39 g (approximately).