Question

1.an object of volume v is immersed in a liquid of density p. calculate the magnitude of buoyant force acting on the object due to the liquid.

2. state the principle on which the working of hydrometers is based.

Answer 1

(1) The buoyancy force = weight of liquid displaced = (mass of liquid displaced = (volume )(density)g = pvg ; where p is the density of liquid, m is the mass of liquid, and g is the acceleration due to gravity.
(2) The working of hygrometer is based on Archemedes principle which states that when an object is immersed partially or fully in liquid then loss of weight of body is equal to the weight of liquid displaced by object.