Question

A solid weighs 32 gf in air and 28.8 gf in water. Find: (i) The volume of solid, (ii) R.D. of solid and (iii) The weight of solid in a liquid of density 0.9 g cm^-3. 

Answer 1

Weight of solid in air , W₁ = 32 gf

Weight of solid when completely immersed in water W₂ = 28.8 gf

(i) Volume of solid = Mass / density of solid

= `32/10` = 3.2 m³

(ii) R.D. of solid = `W_1/(W_1 - W_2) xx "R.D. of water"`

R.D. of solid = `32/(32 - 28.8) xx 1`

R.D. of solid = 10

(iii) Weight of solid in liquid fo density 0.9 gcm^-3 = W₃

R.D. of solid = = `W_1/(W_1 - W_3) xx "R.D. of liquid"`

or , 10 = `32/(32 - W_3) xx 0.9`

or , `W_3` = 29.12 gf