Archimedes....

[Rockter]

A : If I stand on the end of my boat and pee into Loch Ness, does the water in the loch go up, go down, or stay the same?

B : If I take a floating object from below, and throw it overboard, does the water in the loch go up, go down, or stay the same?

C : If I take a naturally-sinking object from below, and throw it overboard, does the water in the loch go up, go down, or stay the same?

D : If I had Loch Ness on the moon, would my boat float higher, lower, or stay the same?

E : If I heated the water in Loch Ness, and drained off the excess that spilled over the loch level control, would my boat be floating higher, or lower at the water line?

F : If I heated the boat only, would my boat be floating higher, or lower at the water line?

This is Loch Ness....

Loch Ness Map

....there ar 7.5 billion tons of water in this great loch.

[sailingdog]

A/B/C—stay the same.... but again, the boat will rise a tiny bit... since it now displaces less water.

D—stay the same, since gravity has changed for everything... at least until the water boiled off due to being in vacuum...

E—Lower—warm water is less dense than cold water... but you'd really piss off Nessie...

F—It depends... some materials contract when heated—they would float lower...since the boat is contracting, it has to sink to displace the same mass of water; others expand when heated—they would float higher... since they're expanding and displacing more water..

[badsanta]

Good job SD.

[sailingdog]

thanks badsanta.

Now to complicate things... say you have a crew member bring two cases of beer aboard the boat from the local package/liquor store...

What happens to the boat—does it sink or rise?
What happens to the Loch—does it rise, fall or stay the same?

[AdamLein]

Answer for C is not that simple. When you throw a sinking object overboard, unless it is perfectly rigid it will contract with increasing water pressure as it sinks, and therefore displace less water, so the Loch's level with drop.

[AdamLein]

Originally Posted by sailingdog

thanks badsanta.

Now to complicate things... say you have a crew member bring two cases of beer aboard the boat from the local package/liquor store...

What happens to the boat—does it sink or rise?
What happens to the Loch—does it rise, fall or stay the same?

Also, what happens when the beer is drunk and the dissolved gasses are belched out? Does the boat sink or rise?

[timebandit]

What if the monster eats you?
Will the Loch change color?

[badsanta]

Stays the same till you pee overboard!!

[sailingdog]

After re-thinking it, Adam's right, but it also depends on the density of the object... if the object is really dense, like a solid cube of osmium, the loch's water level will actually go down—since the boat is now displacing less water—equivalent to the mass of the object, but the water level has only rising by the volume of the object itself. The higher the density of the object, the more the loch's level will drop.

Originally Posted by AdamLein

Answer for C is not that simple. When you throw a sinking object overboard, unless it is perfectly rigid it will contract with increasing water pressure as it sinks, and therefore displace less water, so the Loch's level with drop.

[Joesaila]

If we send too much mass to the moon, earth will become lighter and go out of orbit. So we have to be careful because 8.3 lbs per gallon times volume of Loch Ness could spend trouble. Esp when the toad lickers find out... [lets not forget to be at least 3 miles out too if we want to pee]