The handle of a metal spoon warms up when it is placed in a hot bowl of soup because of radiation. conduction. convection. insulation.
The correct answer and explanation is:
Correct Answer: Conduction
Explanation (300 words):
When a metal spoon is placed in a hot bowl of soup, the handle of the spoon gradually warms up. This phenomenon occurs due to conduction, which is the transfer of heat through a solid material from one particle to another.
Conduction happens when molecules or atoms in a substance with higher energy (heat) collide with neighboring molecules that have lower energy. In the case of the spoon, the part submerged in the hot soup absorbs thermal energy. The metal atoms in that part begin to vibrate more rapidly due to the increased thermal energy. These vibrations then transfer from one atom to the next along the spoon’s length, causing the entire spoon—including the handle—to gradually warm up.
Metal is an excellent conductor of heat because it has free electrons that move easily throughout the structure. These electrons carry thermal energy efficiently from the hotter part (in the soup) to the cooler part (the handle). This is why the handle becomes warm relatively quickly.
Let’s consider why the other options are incorrect:
- Radiation is the transfer of heat through electromagnetic waves, such as from the Sun to the Earth. It does not require a medium and typically affects surfaces exposed to infrared energy. It is not the primary method in this case.
- Convection involves the movement of fluids (liquids or gases) where warmer, less dense parts rise and cooler, denser parts sink. While soup itself may experience convection, it does not explain the heating of the spoon’s handle.
- Insulation is a method used to prevent heat transfer, often by using materials that conduct heat poorly. Since the spoon is metal—a good conductor—it does the opposite of insulation.
In summary, the warming of a spoon’s handle in hot soup is a classic example of conduction.