Question

a solid weighs 80g in air, 68g in water and 60g in oil. calculate its relative density

Answer 1

The relative density of an object is equal to the ratio of its weight in air and the difference of its weight in air and its weight when the object is submerged in water.

D = [(Wa)/(Wa−Ww )]

From the given data D = [80/(80−68)]

⇒D = (80/12)
⇒D =6.67.

Relative density of oil can be calculated as,
⇒Relative density of oil = Loss in weigh in oil/ Loss in weigh in water
⇒Relative density of oil = (80 – 60 )/(80 − 68)
⇒Relative density of oil = 20/12
⇒Relative density of oil = 1.67

Answer 2

Weight of solid in air, wa = 80 gWeight of solid in water, ww = 68 gWeight of solid in oil, wo = 60 g

 relative density =wa-wo/wa-ww
                           =20/12
                           =1.67

Therefore, the relative density of oil is 1.67