400 kg of water is heated from `30^(@) C ` to `100^(@)C` . What will be the increase in mass of water ? Take specific heat of wateer ` = 4.2 xx10^(3) " J kg"^(-1).^(@)C^(-1)` .

Explanation

To find the increase in mass of water when 400 kg of water is heated from 30°C to 100°C, we can use the principle of energy conservation and Einstein's mass-energy equivalence principle. Here’s a step-by-step solution:

### Step 1: Calculate the heat energy required to heat the water
The formula for calculating the heat energy (Q) required to change the temperature of a substance is given by:
\[ Q = m \cdot s \cdot \Delta T \]
where:
- \( m \) = mass of the water = 400 kg
- \( s \) = specific heat of water = \( 4.2 \times 10^3 \, \text{J/kg°C} \)
...