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प्रश्न
The relative density of lead is 11.3. Its density is ______ g cm–3or ______ kg m–3.
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उत्तर १
The relative density of lead is 11.3. Its density is 11.3 g cm–3or 11.3 × 10-3 kg m–3.
Explanation:
Relative density of a lead is given by the relation,
`"Relative density" = "Density of lead"/"Density of water"`
Density of water = 1 g/cm3
Density of lead = Relative density of lead x Density of water
= 11.3 × 1
= 11.3 g/`"cm"^-3`
Again 1g = `1/1000` kg
`1 cm^3 = 10^(-6)"m"^3`
`1 "g/cm"^3 = 10^(-3)/10^(-6) "kg"/"m"^3 = 10^-3 "kg/m"^-3`
`:. 11.3 "g/cm"^-3 = 11.3 xx 10^-3 "kg/m"^-3`
उत्तर २
Density = 11.3 g/cm3
=11.3 × 103 kg m-3 [1 kg =103 g, 1 m = 102 cm]
=11.3 × 103 kg m-3
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