3 Polystyrene foam is less dense than water. Molly measured the volume of a
small block of foam by submerging it in water in a measuring cylinder.
The pictures show her results.
Forces in action
cm3
240
-220
cm3
240
220
200
180
160
140
-120
100
cm3
240
-220
-200
-180
160
140
120
100
80
60
200
180
160
140
120
100
80
60
water
80
160
40
20
steel
40
20
40
20
polystyrene
