Question

12. What is the mass of a metal sphere of radius 3.0 cm, if its density is 7.0 g/cm3? Express your answer in kg too​

Answer 1

Answer:

The mass of a metal sphere = 792 g

in kgs = 0.792 kg

Explanation:

Given:

Radius of a metal sphere = 3 cm

Density of a metal sphere = 7 g/cm³

To find:

The mass of a metal sphere.

Solution:

Here, we will simply use the formula of mass when density and volume are given. We will find the volume of a metal sphere by using formula of a volume of a sphere. Putting the values in the formula and then doing the required calculations.

✰ Mass = Density × Volume

( N.B: Volume of sphere = 4/3 πr³

Where,

r is the radius of a metal sphere. )

Putting the values,

Mass of a metal sphere = 7 × 4/3 × 22/7 × 3³

Mass of a metal sphere = 7 × 4/3 × 22/7 × 3 × 3 × 3

Mass of a metal sphere = 7 × 4 × 22/7 × 3 × 3

Mass of a metal sphere = 4 × 22 × 3 × 3

Mass of a metal sphere = 88 × 9

Mass of a metal sphere = 792 g

Expressing it in kg...

1 g = 1/1000 kg

792 g = 792/1000

= 0.792 kg