On dry land, an athlete weighs 70.8 kg . The same athlete, when submerged in a swimming pool and hanging from a scale, has an "apparent weight" of 2.70 kg .

Question

On dry land, an athlete weighs 70.8 kgkg . The same athlete, when submerged in a swimming pool and hanging from a scale, has an "apparent weight" of 2.70 kgkg .

Find the total volume VV of the submerged athlete.

Express your answer to three significant figures and include the appropriate units.

Answer 1

apparent weight = actual weight - force of bouyancy(Fb)

2.7*g = 70.8*g - Fb

Fb = 68.1*g kg

as we know that force of bouyancy is due to the weight of water displaced by the athlete

also Fb is given by,

Fb = V*rho*g

where V = volume of body submerged

rho = density of water

therefore putting in the equation

68.1*g = V*1000*g

V = 0.0681 m^3