Question

A heavy ship floats in water because

• A. Its density is less than that of water
• B. Its relative density is less than that of water
• C. Its average density is less than that of water
• D. Its density is equal to that of water

Answer 1

The correct option is C Its average density is less than that of water

Answer is C.
A ship floats because its average density is relatively small. This empty military transport ship is effectively a giant empty metal box. When we divide its total mass (its own mass plus that of its contents) by its volume and we get its average density. That's less than the density of a solid metal box or a metal box filled with water, and that's why the ship floats.
Hence, a heavy ship floats in water because its average density is less than that of water.