Question

student exploration: density experiment: slice and dice
vocabulary: density, mass, matter, volume
prior knowledge questions (do these before using the gizmo.)
1 what do you think would happen if you threw a block of polystyrene (styrofoam™) into the water?
2 what would happen if you broke the styrofoam up into lots of pieces, then threw the pieces into water?
3 what would happen if you threw a big rock into water?
4 what would happen if you broke the rock into little pieces, then threw the pieces into water?
gizmo warm - up
the density experiment: slice and dice gizmo allows you to compare different - sized pieces of the same material.
1 check that polystyrene is selected. drag the whole polystyrene piece into the water.
does it sink or float?
2 click reset, and then click slice to cut the polystyrene into pieces. drag each piece into the water and then back to the block.
what happens?
3 how do you think the amount of a material affects its tendency to sink or float?

Explanation:

1. Polystyrene is less dense than water, so it would float as a whole block.
2. Breaking it into pieces doesn't change its density, so the pieces would also float.
3. A big rock is denser than water, so it would sink.
4. Breaking the rock into pieces doesn't change its density - related property of being denser than water, so the pieces would sink. In the Gizmo warm - up: 1. The whole polystyrene piece floats as it is less dense than water. 2. The pieces of polystyrene float too as density is a characteristic property not affected by size. 3. The amount of a material doesn't affect its tendency to sink or float as long as its density relative to the liquid remains the same.

Answer:

1. It would float.
2. The pieces would float.
3. It would sink.
4. The pieces would sink.

Gizmo Warm - up 1. Float.
Gizmo Warm - up 2. The pieces float.
Gizmo Warm - up 3. The amount of a material does not affect its sinking or floating tendency as long as its density relative to the liquid stays the same.