What will happen to the water temperature if a hot iron is placed in water?

What will happen to the water temperature if a hot iron is placed in water?

• A. Increase
• B. Decrease
• C. Remain the same
• D. Oscillate

Answer: (A)

When a hotter object comes into contact with cooler water, heat flows from the hot object to the cooler one. Since the iron is hotter than the water, energy moves into the water, raising its temperature. As the iron loses heat, it cools down, and both approach the same final temperature. The water ends up warmer than it started, not cooler, not unchanged, and not oscillating. How much the water warms depends on how much heat the iron can give up and how much water can absorb it (their masses and specific heat capacities).

When a hotter object comes into contact with cooler water, heat flows from the hot object to the cooler one. Since the iron is hotter than the water, energy moves into the water, raising its temperature. As the iron loses heat, it cools down, and both approach the same final temperature. The water ends up warmer than it started, not cooler, not unchanged, and not oscillating. How much the water warms depends on how much heat the iron can give up and how much water can absorb it (their masses and specific heat capacities).