An empty density bottle has a mass of 23g. When completely filled with water its mass is 39.0g. What will be its mass if it is completely filled with an acid of relative density 1.25? (Take the density of water as 1.Ogcm-3)

Explanation:

in short : the mass goes linearly with the density.

the mass of the bottle filled with that acid is

the mass of the bottle itself (23g) plus the acid filling, which 1.25 times more dense than the water filling.

the water filing itself had a mass of 39 - 23 = 16g

the acid filing has therefore a mass of 16×1.25 = 20g

so, in total, the bottle filled with the acid has a mass of

23 + 20 = 43g

the force required to move the cart is divided by three or 33.33 n.

the answer is b, have negligible mass