Question 23
Quantity of HeatA mass of a liquid at 30 °C is mixed with a mass of the same liquid at 70 °C and the temperature of the mixture is 45 °C. Find the ratio of the mass of the cold liquid to the mass of the other liquid.
- A.3 : 5
- B.5 : 3
- C.3 : 7
- D.7 : 3
Show the answer and explanation
Answer: B (5 : 3)
Explanation
Heat gained = heat lost: mc × 15 = mh × 25, so mc : mh = 25 : 15 = 5 : 3.