Personal Comment: Lead is pretty heavy but does it displace much water?

Lead Brick Enigma

What we know: Eric is sitting in a boat on a pond carrying a lead brick. Using his extensive physics knowledge, he figures that since he has such huge thighs, he may want to throw the brick overboard so he does not sink like the Titanic did. He watched the movie 7 times so he knows it would not be fun, although now he is in 10 feet of luke-warm water. Anyway, he throws the brick over.

Enigma: Does the water level of the pond rise, fall, or stay the same? (HINT: When the brick is in the boat, it displaces as much water as the WEIGHT of the brick...When it is in the water it displaces as much water as the VOLUME of the brick)

Solution: The water level drops!

Reason: Lead is much more dense than water. In the boat, the brick displaces a volume of water equal to the weight of the brick, a volume much larger than the brick itself. In the water, the displacement is merely the volume of the brick.

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