Question

An object weighs 12N in air when immersed fully in tap water it weighs 10N.
a) Find the weight of liquid displaced by the object.
b) Is is the weight of body when immerses in salty water is less than or greater than or equal to 10N. why..??​

Answer 1

a) 2N

b)weight will be less in salty water, because upthrust acting on it will be more in salty water as upthrust=Volume *density*g

and density of salty water is more than normal water

Calculation-Wise explanation-

Upthrust in tap water = Loss in weight of body= 12N-10N= 2N

So 2N = Volume of body * Density of liquid * acceleration due to gravity

Volume of Body and g will be same but in salty water ,density of liquid will increase and so upthrust will be more than 2N.

And so Apparent weight will be less as it is true weight - upthrust