An object has a volume of 4.0 cm(Cubed) and weighs 40,000 N. What will be it's apparent weight in water?

Question

This is not a homework question. i am merely posting this on here in hopes that you guys can settle a bet between a friend of mine.

Answer 1

The bouyant force is equal to the weight of the displaced fluid. Water has a density of 1 gram per cm cubed and you displaced 4 cm^3, so the bouyant force is equal to the weight of 4 grams.

F = mg = (.004 kg)(9.8 m/s^2) = about .04 N

So the apparent weight in water is still 40,000 N; the bouyant force is negligible in this problem.

By the way, there's no material on earth with a density of 1000 kg per cubic centimeter.