Question

You have a bag of cotton and an iron bar each indicating a mass of 100kg when measured on a weighing machine.in reality one is heavier than other.can you say which one is heavier and why?

Answer 1

The iron bar is heavier than the bag of cotton. This is because the surface area of thecotton bag is larger than the iron bar. Hence, more buoyant force acts on the bagthan that on an iron bar. This makes the cotton bag lighter than its actual value. Forthis reason, the iron bar and the bag of cotton show the same mass on the weighingmachine, but actually the mass of the iron bar is more that that of the cotton bag

Answer 2

both are same the mass of each is 100kg but weight of two may not be same.this is because as the cotton is porous and can have some air inside its pores as well as its volume will be considerable