Question

The diameter of a lead ball is 2.1 cm. The density of the lead used is 11.34 g/c?. What is
the weight of the ball?​

Answer 1

Solution :-

The diameter of a lead ball = 2.1 cm

Therefore,

Radius of the lead ball = 2.1/2 = 1.05 cm

Now,

As we know that,

The volume of the sphere = 4/3πr^3

The volume of the sphere

= 4 / 3 * 22/7 * 1.05 * 1.05 * 1.05

= 4 * 22 * 0.35 * 0.15 * 1.05

= 4 * 22 * 0.0525 * 1.05

= 88 * 0.0525 * 1.05

= 4.851 cm^3

Now,

Lead used for making lead ball = 11.34g/c

Therefore,

The weight of the lead ball = 11.34 * 4.851

The weight of the lead ball = 55.01g

Hence, The weight of the ball

= 55.01g$.$

Answer 2

$\huge \underline \bold \purple{Solution}$

The diameter of a lead ball = 2.1 cm

Therefore,

Radius of the lead ball = 2.1/2 = 1.05 cm

Now,

As we know that,

The volume of the sphere = 4/3πr^3

The volume of the sphere

= 4 / 3 * 22/7 * 1.05 * 1.05 * 1.05

= 4 * 22 * 0.35 * 0.15 * 1.05

= 4 * 22 * 0.0525 * 1.05

= 88 * 0.0525 * 1.05

= 4.851 cm^3

Now,

Lead used for making lead ball = 11.34g/c

Therefore,

The weight of the lead ball = 11.34 * 4.851

The weight of the lead ball = 55.01g

Hence, The weight of the ball

= 55.01g