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Density and relative density

Table 4.1: Densities of common substances
Solids Substance Aluminium Copper Gold Iron Lead Glass Ice
(0 °C)
Density 2 700 8 800 19 300 7 800 11 300 2 500 920
(kg/m )
3
Liquids Substance Seawater Water Water Gasoline/
(4 °C) (20 °C) petrol
Density 1 030 1 000 998 700
(kg/m )
3
Gases Substance Air Carbon Hydrogen Helium
(at standard dioxide
conditions)
Density 1.225 1.98 0.820 0.178
(kg/m )
3

Acti vity 4.1
Aim: To determine the mass to volume ratio for given objects.
Materials: Vernier calliper, beam balance, three identical blocks of different
materials as shown in Figure 4.4 (for instance, aluminium, copper, and
iron, respectively)

Aluminium Copper Iron
Figure 4.4
Procedure
1. Measure the length, height and width of each object.
2. Measure the mass of each block.
3. Record all observations using the following table.
Table 4.2
Substance Length Height Width Mass (g) Volume m
(cm) (cm) (cm) (cm ) V
3
Aluminium
Copper
Iron

Questions
(a) Compare the mass to volume ratio of each substance.
(b) Are they different or the same? Why?
(c) What physical quantity does the ratio represent?

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Physics Form 1 Final.indd 79 16/10/2024 20:56