How do you determine the density of an irregularly shaped object?

• A. Weigh the object and divide its mass by the volume of the container.
• B. Submerge the object in water to measure the displacement, then divide its mass by the displaced volume.
• C. Measure the object's height, width, and depth and compute volume.
• D. Compare with known densities on a chart.

Answer: (B)

Density is mass divided by volume. For an irregularly shaped object, you determine its volume by water displacement: submerge the object in a graduated cylinder filled with water and note how much the water level rises. The increase in volume equals the object's volume. Then weigh the object to get its mass and divide the mass by the displaced volume to get density. This follows Archimedes’ principle and works because the displaced water volume directly measures how much space the object occupies. Use consistent units (grams and milliliters or kilograms and liters) so the density is in g/mL or kg/m^3. The other methods either use the container’s volume, rely on dimensions that don’t apply to irregular shapes, or compare to a chart without measuring actual mass and volume.