10 g of water at `70^@C` is mixed with 5 g of water at `30^@C`. Find the temperature of the mixture in equilibrium. Specific heat of water is `1 cal//g.^@C`.

Explanation

To find the equilibrium temperature when 10 g of water at 70°C is mixed with 5 g of water at 30°C, we can use the principle of conservation of energy, which states that the heat lost by the hot water will be equal to the heat gained by the cold water.

### Step-by-Step Solution:

1. **Identify the masses and temperatures:**
- Mass of hot water (m1) = 10 g
- Initial temperature of hot water (T1) = 70°C
- Mass of cold water (m2) = 5 g
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