Physics
A piece of a cake and a watermelon of the same mass are taken out of the freezer at the same time. Which of the following statement is correct?
- Cake and watermelon will attain the room temperature at the same time.
- Watermelon will attain the room temperature faster.
- Cake will attain the room temperature faster.
- Which one comes to the room temperature first, depends on the atmospheric pressure at that time.
Answer
Cake will attain the room temperature faster.
Reason — The rate at which an object warms depends, among other factors, on its specific heat capacity. Watermelon consists mainly of water, whose specific heat capacity is high (about 4.2 J g-1 °C-1). Cake contains far less water and more fats and carbohydrates, whose specific heat capacities are roughly half that of water. Therefore, for the same mass and under identical external conditions, the cake requires less heat to raise its temperature by 1 °C and will reach room temperature sooner than the watermelon.
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