Question

Students want to investigate convection. Which of the following experimental setups would best allow them to observe convection?

A. A white box and a black box are set up under heat lamps with thermometers to record how the temperature changes over time.
B. Three rods made of three different materials are placed in hot water, and the change in their temperature is recorded over time.
C. A beaker of cold water is placed on a hot plate. A drop of food coloring is dropped into the center of the water, and motion is observed.

Answer 1

The best setup to observe convection is option C, where a beaker of cold water is heated and a drop of food coloring shows the convection currents.

Step-by-step explanation:

To investigate convection, the most suitable experimental setup among the given options is option C. In this setup, a beaker of cold water is placed on a hot plate, and a drop of food coloring is added. As the water heats, the motion caused by the increase in temperature can be observed by watching how the food coloring disperses throughout the water. This directly demonstrates convection currents, as the warmer water rises and cooler water descends, creating a visible circulation pattern in the beaker. This experiment is similar to the suggested take-home experiment involving convection rolls in a heated pan, where two pots of water are used to observe the spreading of food coloring and the formation of convective loops when heat is applied.