Page 111 - Physics

Sinking and fl oating

Acti vity 5.5
Aim: To determine the relative density of a solid that fl oats in water.

Materials: Cork, stone (sinker), spring balance, string, beaker and water

Procedure
1. Tie a stone with a string and suspend it from a spring balance. Record its weight
as w .
1
2. Immerse the stone in a beaker that contains water as shown in Figure 5.7 (a).

(a)
(a) (b)
(c)
(c)

Spring
Spring Spring
Spring
balance
balances
balances balance

Cork
Cork

Cork
Water
Stone
Stone

Figure 5.7
3. Record its apparent weight as w .
2
4. Using the same string, tie the cork so that it is above the stone.

5. Immerse the stone in water while the cork is in the air shown in Figure 5.7 (b).
6. Record their weight as w .
3
7. Immerse both the stone and the cork in the water shown in Figure 5.7 (c) and
record their combined weight as w .
4
Questions

(a) What is the function of a stone?
(b) From your results, fi ll in the following blanks.

105

Physics Form 1 Final.indd 105 16/10/2024 20:56