Objective
To construct several models to demonstrate the principle of convection, and to use your observations to explore
the role convection plays in the development of atmospheric circulation and ocean currents.
Materials Needed per Lab Group:
To construct several models to demonstrate the principle of convection, and to use your observations to explore
the role convection plays in the development of atmospheric circulation and ocean currents.
Materials Needed per Lab Group:
- 1 Clear Plastic Box
- 1 Beaker, 50 ml
- 1 Wood Block
- 2 Pipettes
- 6 Styrofoam Cups
- 8 Plastic Lids (spacers)
- 1 Plastic Spoon
- Student Study and Analysis Sheets
- Food Coloring
- Salt
- Water (hot and cold)
- Ice Cubes
- Graduated Cylinder, 100 ml
- Colored Pencils
- Periodic Table
Procedures:
1. Fit two plastic lids on each of 4 Styrofoam cups. Set the clear plastic box onto the four Styrofoam cups
as shown in figure 2. Carefully fill the box with cold tap water to within 3-4 cm from the top. Let the water calm before proceeding.
2. Using the pipette, carefully place 3 spots of red food coloring on the bottom of the box as shown in figure 2. Insert the pipette all the way down to the bottom of the box before squeezing out the dye. Each spot should be about 2-4 cm in diameter. Try to minimize disturbing the water as you insert and remove the pipette.
3. Fill one empty Styrofoam cup with hot water and then carefully position it beneath the center dye spot.
The plastic lid spacers you fitted on the corner cups should provide you with enough clearance to gently
slide the cup with to water under the spot.
4. Now position yourself so that you can view the box from the side at eye level, and observe what
happens to the 3 spots over the next 5 minutes. Be sure to look for changes in all 3 spots. Write your
observations below.
5. Sketch what you observed in diagram 1 below. Use arrows to show the direction of flow.
6. Using two hands under the box, carefully empty the water into a sink and begin Setup B.
1. Fit two plastic lids on each of 4 Styrofoam cups. Set the clear plastic box onto the four Styrofoam cups
as shown in figure 2. Carefully fill the box with cold tap water to within 3-4 cm from the top. Let the water calm before proceeding.
2. Using the pipette, carefully place 3 spots of red food coloring on the bottom of the box as shown in figure 2. Insert the pipette all the way down to the bottom of the box before squeezing out the dye. Each spot should be about 2-4 cm in diameter. Try to minimize disturbing the water as you insert and remove the pipette.
3. Fill one empty Styrofoam cup with hot water and then carefully position it beneath the center dye spot.
The plastic lid spacers you fitted on the corner cups should provide you with enough clearance to gently
slide the cup with to water under the spot.
4. Now position yourself so that you can view the box from the side at eye level, and observe what
happens to the 3 spots over the next 5 minutes. Be sure to look for changes in all 3 spots. Write your
observations below.
5. Sketch what you observed in diagram 1 below. Use arrows to show the direction of flow.
6. Using two hands under the box, carefully empty the water into a sink and begin Setup B.
1. During the lab, what effect did the cups of hot water have on the density of the water directly above
them? (hint: think about particles moving)
The density weny down, it decreased.
2. What happened as a result of this change?
the dye rose and the density
3. You may have noticed convection cells in a pot of boiling macaroni. Put arrows on the dashed lines in Figure 4 to show the direction of the flow in the pot. The hottest part of the burner is beneath the center of the pot.
them? (hint: think about particles moving)
The density weny down, it decreased.
2. What happened as a result of this change?
the dye rose and the density
3. You may have noticed convection cells in a pot of boiling macaroni. Put arrows on the dashed lines in Figure 4 to show the direction of the flow in the pot. The hottest part of the burner is beneath the center of the pot.