Question

A solid weighs 100g in air,75g in water and 70g in oil.Calculate the relative density of oil.

Answer 1

It has mass of 100 g

It lost 25 g in water so its volume is 25 cm^3

It lost 30 g in oil so the mass of oil displaced by its 25 cm^3 volume was 30 g

so density of the oil = 30 g/25cm^3
= 1.2 g/cm^3 = 1.2 times water density.

Answer 2

By the way most oil floats on water :)

Answer 3

So you considered oil as mass right?

Answer 4

The unit for Density is kg/m^3

Answer 5

Very important otherwise you lose 1 mark

Answer 6

But it seems the calculation is wrong bcw Density= Mass÷Volume