Item CL016002: Warm air around an electric heater will rise toward the ceiling, move toward the walls, and then sink back to the floor.

The heater in the room shown below is continuously warming the air around it so that the air near the heater is much warmer than the air in the rest of the room.

What happens to the air around the heater as it is warmed?

  1. It rises toward the ceiling and stays there.
  2. It rises toward the ceiling, but it does not stay there. It moves toward the walls before it eventually sinks back down to the floor.
  3. It rises toward the ceiling, but it does not stay there or move toward the walls. Instead, it sinks back down to the floor.
  4. It moves away from the heater in all directions until it fills the room.
Distribution of Responses
Chart showing distrubtion of responses for Item CL016002
Students Responding Correctly
Group Correct Total Percent
Overall 726 2106 35%
  6–8 325 1029 32%
  9–12 399 1067 37%
Primary Language

View data table

NGSS does not include the idea that cold air sinks and warm air rises or why that occurs. It does address the role that density and temperature differences play in creating ocean currents, which is an analogous process (see Framework statement MS ESS2.C on p. 185).