If the yachtsman throws overboard ;
a. A buoy ?
b. An anchore ?
a. A buoy ?
b. An anchore ?
-
a. By Archimedes principle , the buoy displace its own weight of water whether inside or outside the yacht. so the level of water remains unchanged .
b. The anchor displaces its own weight of water when inside the boat . but less when it sinks (it just displaces its own volume of water which weighs less) . so the water level drops.
b. The anchor displaces its own weight of water when inside the boat . but less when it sinks (it just displaces its own volume of water which weighs less) . so the water level drops.
-
A floating object displaces its own weight of water. A submerged object displaces its own volume of water.
Whilst the two objects are in the boat, they are both floating, and therefore displacing their own weight of lake water, which sets the level of water in the lake.
When the buoy is thrown overboard, it continues to float, so the level of water is not affected.
{The boat without the buoy's weight load on board displaces slightly less water, which exactly matches the displacement of the overboard buoy}
The anchor sinks when it is thrown off the boat and therefore now displaces its own volume of water, instead of loading the boat down by an amount which displaces the anchor's weight of lake water.
The density of the anchor is greater than the density of water {otherwise it wouldn't sink!} so its volume is less than the volume of the same weight of water.
The level of water in the lake will therefore go down slightly when the anchor is thrown overboard.
Whilst the two objects are in the boat, they are both floating, and therefore displacing their own weight of lake water, which sets the level of water in the lake.
When the buoy is thrown overboard, it continues to float, so the level of water is not affected.
{The boat without the buoy's weight load on board displaces slightly less water, which exactly matches the displacement of the overboard buoy}
The anchor sinks when it is thrown off the boat and therefore now displaces its own volume of water, instead of loading the boat down by an amount which displaces the anchor's weight of lake water.
The density of the anchor is greater than the density of water {otherwise it wouldn't sink!} so its volume is less than the volume of the same weight of water.
The level of water in the lake will therefore go down slightly when the anchor is thrown overboard.
-
While the anchor is in the boat it displaces enough water to equal it's weight (Archimedes principle) .. this is a greater volume of water than the volume of the anchor as the density of water is less than iron.
With the anchor overboard the water level (in theory) drops as the sunken anvil displaces less water than it did in the boat - overall there is less water displaced so the level drops.
There is no change to the water level when the buoy is floating in the water .. whether in the boat or floating it displaces the same amount of water .. enough to equal it's own weight.
With the anchor overboard the water level (in theory) drops as the sunken anvil displaces less water than it did in the boat - overall there is less water displaced so the level drops.
There is no change to the water level when the buoy is floating in the water .. whether in the boat or floating it displaces the same amount of water .. enough to equal it's own weight.
-
To the lake's water level or the yacht's ?