Question

3. 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 cm??​

Answer 1

Given:

Diameter = 4.2cm

Density = 8.9g per cm

Mass = ?

Solution:

Density = Mass/Volume

Mass = Density x Volume

Volume of sphere = 4/3πr³

(r = d/2 = 4.2/2 = 2.1cm)

Volume = 4/3 x 22/7 x (2.1)³

= 38.8 cm³

Now,

Mass = 8.9 x 38.8

= 345.3g

Answer 2

✦ 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 cm?

Answer :-

$\therefore\underline{\boxed{\textsf{M = {\textbf{345.3g}}}}} \qquad\qquad \bigg\lgroup\bold{Mass \ of \ the \ ball} \bigg\rgroup$

Given:

Diameter of a metallic ball is 4.2cm

Density of the metal is 8.9g per cm

Have to find :-

What is the mass of the metallic ball ?

$\Large{\underline{\underline{\bf{Calculations:-}}}}$

As according to the Question :-

Ball is in sphere shape .

So , Volume of sphere is 4/3πr³

So , substituting the values from given

Volume of sphere ↠ 4/3 x 22/7 x ( 2.1 )³

↠ 38.8 cm³

Therefore ,

As we know the formulas of the Density :-

From this we get ,

Mass ↠ Density x Volume

↠ 8.9 x 38.8

↠ 345.3g { The required Answer }