Question

A block of iron has dimensions 2 m x 0.5 m x 0.25 m. The density of iron is 7.8 g/cm³. Find the mass of the block.

• A. 19.50 g
• B. 1950 kg
• C. 1.95 kg
• D. 200 g/cm³

Answer 1

The correct option is B

1950 kg

Given:

Dimensions = 2 m × 0.5 m × 0.25 m
Density, d = 7.8 g/cm³

Volume, V = 0.25 m³

1 g cm-3 = 10,00,000 g/m³

Density, d = 7.8 × 10,00,000 g/m³
= 78,00,000 g/m³

Since, d = m/V; m= V × d

Hence,
the mass of the block , m =
= 0.25 m³ × 78,00,000 g/m³

= 19,50,000 g
= 1950 kg