Question

A solid weighs 80 GF in air and 60 GF when completely immersed in water calculate (a) upthrust (b) volume of the solid (c) relative density of the solid (d) density of the solid in SI unit ​

Answer 1

Question-

A solid weighs 80 GF in air and 60 GF when completely immersed in water calculate

(a) upthrust

(b) volume of the solid

(c) relative density of the solid

(d) density of the solid in SI unit ​

Answer-

Given, the weight of solid in air W1 = 50 gf and weight of solid in water w2 = 44 gf

(a) Upthurst = loss in weight when immersed in water = W1 - W2 = 80 - 60 = 20 gf

(b) Weight of water displaced = upthurst = 20 gf

Since the density of water is 1 g/m³, therefore the volume of water displaced = 20cm³

But the solid displaces water equal to its own volume, therefore the volume of solid = 20cm³

(c) R.D. of solid = Weight of solid in air / Weight in the air - Weight in water

= W1 / W1 - W2 = 80 / 80 - 60 = 80 / 20 = 4

(d) The SI unit of density is the kilogram per cubic meter [kg/m³].

= 4kg/m³