Mercury, a metal that is liquid at room temperature, has a density 13.5 times the density of water. How many pennies could your boat hold if we were floating it in mercury instead of water?

Question

Mercury, a metal that is liquid at room temperature, has a density 13.5 times the density of water.  How many pennies could your boat hold if we were floating it in mercury instead of water?

anonymous · Answer

how many does it hold in water?

anonymous · Answer

30

anonymous · Answer

so since Hg is 13.5 times denser than $H_2O$ it makes sense that it will take 13.5 times more weight to get the same displacement, yeah?

and how would you get 13.5 times the weight?

anonymous · Answer

do you understand?

anonymous · Answer

not really..

anonymous · Answer

any help? Do you know the answer?

anonymous · Answer

suppose a boat floating in water can hold 1 lb.  if the same boat were floating in a liquid that was twice as dense as water, it could hold 2 lbs, twice as much.

the same thing applies in your problem.  your boat can hold 30 pennies is water.  in mercury, which is 13.5 times as dense as water, your boat could hold 13.5 times as many pennies.

the reason is that the mercury is 13.5 times as buoyant as water.