A group of students built a model of the water cycle inside a fish tank. They added rocks, soil, and small plants around a bowl of water in the center. The students created a stream in their model by cutting a small hole in the top of their aquarium and using a tube to run water over the rocks to their bowl “lake.” They recorded their observations of the model for two weeks.

Question

When they compared their observations, the students all agreed that something was missing. Aside from the water flowing into the model from the stream, they did not observe water cycling fully through the system. They observed runoff and infiltration over the two-week period.

What could the students add to the model that could help them observe the evaporation of water?

A.
The students could add a heat lamp to the model to simulate the sun's energy.


B.
The students could add ice cubes to the lake to change the thermal energy in the model.


C.
The students could add more plants to the model to increase the transfer of water between the soil and plants.


D.
The students could add another stream to the model to increase the water in the cycle.

Answer 1

A. The students could add a heat lamp to the model to simulate the sun's energy.

This option would help the students observe the evaporation of water, as heat from the lamp would increase the temperature of the water, promoting evaporation, which is a key part of the water cycle.