How much water is displaced by object A?
Water has a density of 1 gram per cubic centimeter (1 g/cm3). Based on its density, what is the mass of the displaced water?
Use Archimedes’ principle to determine the mass of object A:
Measure: Click Reset. Notice that object F has the same volume as object A. Drag object F into the water.
Does object F float or sink?.
How much water is displaced by object F?
What is the volume of object F?
What is the volume of object A?
Calculate: The density of an object is equal to its mass divided by its volume: D = m ÷ V. The unit of density is grams per cubic centimeter (g/cc or g/cm3).
What is the density of object A?
Analyze: Click Reset and drop object A back into the water. About what percentage of object A is under the water? How is this percentage related to the density of object A?
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Activity (continued from previous page)
Gather data: Click Reset. Find how much water is displaced by objects B, C, D, and E. Record your measurements below. Include units.
Calculate: Use your data to find the mass, volume, and density of the two floating objects, C and E. Recall that the mass of a floating object is equal to the mass of displaced water, and the volume of a sinking object is equal to the volume of displaced water. Assume objects B and E have the same volume, as do objects C and D.
Object C: Mass: Volume: Density:
Object E: Mass: Volume: Density:
Analyze: Drag objects C and E into the water. Estimate the percentage of these objects that are submerged below the waterline. List these estimates below:
Object C: Object E:
How do these estimates relate to the densities you calculated above?
Think and discuss: Why can’t you use this Gizmo to measure the densities of objects B, D, and F? If possible, discuss your answer with your classmates and teacher.
Challenge: What can you say about the densities of objects B, D, and F? Is there a way to compare the relative densities of these three objects? Explain.