The water in an aquarium is warmed by a heater located under the gravel in the bottom of the aquarium. a. Explain how the energy is transferred to the gravel.

The energy transfer from the heater to the gravel in the aquarium occurs through a process called conduction. Here are the steps:

1. The heater generates heat energy. This energy is transferred to the molecules of the heater's material, causing them to vibrate more rapidly.

2. These vibrating molecules then collide with the adjacent molecules in the gravel. When this happens, the energy from the vibrating molecules is transferred to the adjacent molecules.

3. This process continues, with the energy being passed from molecule to molecule through the gravel. This is how the heat from the heater is conducted to the gravel.

4. As the gravel heats up, it in turn heats the water in the aquarium through a similar process of conduction.

5. The heated water then circulates throughout the aquarium, distributing the heat evenly. This is due to the process of convection, where the warmer water rises and the cooler water sinks, creating a continuous circulation of water.

This is a basic explanation of how the energy from the heater is transferred to the gravel in an aquarium.