PSA: Muscles do not weigh more than fat.

Personally I think you're completely wrong. It seems that from your perspective, it would be incorrect to say anything weighs more than anything else. Or at least it would be incorrect to compare weights without specifying volume first. In the phrase "Muscle weighs more than fat" it is implied that we're referencing equivalent volume measurements.

For example, could you say: "A 10lb dumbbell weighs more than a 5lb dumbbell." On the surface it appears to make sense, but according to you it doesn't since 1lb of a 10lb dumbbell is equal to 1lb of a 5lb dumbbell. However, it's implied that we mean exactly 1 full 10lb dumbbell and exactly 1 full 5lb dumbbell.

So yes, when someone says "Muscle weighs more than fat" they really mean "Muscle is more dense than fat" but because of the implication that we're discussing equal volumes, it amounts to the exact same meaning.

It's called buoyancy. Please google it. I am apparently not doing a good job explaining it. Yes, density plays a factor but shape is more important. This is why iron ships float, yet a chunk of iron does not.

And you are "buoyant" if you are less dense than the stuff you're floating in.

A ship is buoyant (boy that's hard to type) when it's enclosing enough air to lower its overall density to less than that of the water it's resting on.

The chunk of iron is clearly enclosing nothing but more iron, therefore is more dense and not buoyant at all.

People are buoyant when their lungs are full of air, regardless of their physical position.

We're talking about the same thing here.

Also: If you took your chunk of iron and flattened it out to super-wide but only paper thin and laid it gingerly on top of the water...?

It would still sink.

When people say "muscle weighs more than fat" there is an implied "by volume". If I say gold weighs more than feathers, everyone knows what that means and the "by volume" is completely unnecessary.

By the OP's logic, one couldn't say "The Eiffel Tower weighs more than my house". After all, a pound of Eiffel Tower equals a pound of my house. Extend the logic to people. I could say that I don't weigh any more than any other person. After all, a pound of them and a pound of me both weigh a pound. We could even apply it to food. Don't you dare say bread has more calories than celery. After all, 100 calories of bread and 100 calories of celery have the same number of calories!

Glad we can re-hash this topic for the millionth time.

1lb of substance "A" isn't heavier than 1lb of substance "B"??? NO WAY!!! GET OUT ----> !!!

Glad we can re-hash this topic for the millionth time.

1lb of substance "A" isn't heavier than 1lb of substance "B"??? NO WAY!!! GET OUT ----> !!!

Maybe the forum search function was down?

Or maybe all of the other 999,999 times this has been discussed before, it spiraled out of control and was mod-deleted so search couldn't find it.

Or more likely, OP was just bored and she knew exactly how this thread would play out.

Yeah, I'm going with that last theory.

7 pages on this? Seriously?

Wrong. Floating on your back has nothing to do with whether you sink or not. If you were to simply hold your breath and orientate yourself verticallly in the water, you would still float just like when you are on your back. The same mass of you would be above the water as when you were on your back. The reason floating on your back is preferred is because it keeps your face out of the water.

Humans, when their lungs are full, do not sink. It's when you exhale or worse displace the air in your lungs with water that you sink as you have changed your density since the air in your lungs was lowering your average density. Try it sometime in a pool.

It's called buoyancy. Please google it. I am apparently not doing a good job explaining it. Yes, density plays a factor but shape is more important. This is why iron ships float, yet a chunk of iron does not.

To push a V-hull boat under water, you have to submerge not just the material in the hull but the air and material contained within it. The density is all of these masses combined divided by volume. It still comes down to density, plain and simple. Perhaps your Google is broken.

What about boats without enclosed hulls? I maintain that floatation is not only dictated by density but by the shape of an object. Pretty sure I learned this in elementary school. I found this on a kids' website:

The object is buoyed up (pushed up) by a force that is equal to the weight of the water that the object occupies that was previously occupied by the water. If you shape the object is in such a way that it occupies a volume of water whose weight equals that of the object, the object will float. If it occupies a volume of water whose weight is less than the weight of the object, the object will sink.

You can show this to yourself by taking a piece of aluminum foil and making a water-tight boat out of it. If you carefully put the boat in a dish or pan of water, you will see it float.

Now take the aluminum foil boat and crumple it up into a ball and put it back on the water. It sinks! There is the same amount of aluminum foil in both cases, but in the case of the boat, you shaped it so that it displaced a lot of water compared to the amount of water that is displaced when you crumpled the aluminum foil into a ball.

What about boats without enclosed hulls? I maintain that floatation is not only dictated by density but by shape of an object. Pretty sure I learned this in elementary school. I found this on a kids' website:

The object is buoyed up (pushed up) by a force that is equal to the weight of the water that the object occupies that was previously occupied by the water. If you shape the object is in such a way that it occupies a volume of water whose weight equals that of the object, the object will float. If it occupies a volume of water whose weight is less than the weight of the object, the object will sink.

You can show this to yourself by taking a piece of aluminum foil and making a water-tight boat out of it. If you carefully put the boat in a dish or pan of water, you will see it float.

Now take the aluminum foil boat and crumple it up into a ball and put it back on the water. It sinks! There is the same amount of aluminum foil in both cases, but in the case of the boat, you shaped it so that it displaced a lot of water compared to the amount of water that is displaced when you crumpled the aluminum foil into a ball.

Like a rowboat, for example?

What it's describing is still density. Imagine putting a layer of saran wrap over the top of the rowboat - you calculate the mass of everything inside the hull - people, coolers, fishing poles, and wood - and how much space it takes up. The ratio of mass to volume is its density.

If it's more dense than the water holding it up, it will push into the water far enough to let the stuff leak in over the hull, and bloop - she sinks.

If it's less dense, then all is well.

The difference between the foil boat and the foil ball is twofold:

1. The ball is smushed smaller, ergo less volume and higher density. (Sink)
2. The boat presumably has walls on it, which encompass air and produce MORE volume for the boat and therefore LOWER density. (Float)

Buoyancy, which I still cannot type to save my soul, is just a word intended to describe the float-or-sink tendency of an object. Whether or not it is buoyant is determined by its overall density.

I will part on this note: Often, websites and texts that are aimed at teaching kids how the world works will gloss over some critical terms and concepts. There still might be, from time to time, more to the story.

[EDIT, because I can never just be DONE with one post...]

"Displacement" can also be considered the same as "volume."

Glad we can re-hash this topic for the millionth time.

1lb of substance "A" isn't heavier than 1lb of substance "B"??? NO WAY!!! GET OUT ----> !!!

Maybe the forum search function was down?

Or maybe all of the other 999,999 times this has been discussed before, it spiraled out of control and was mod-deleted so search couldn't find it.

Or more likely, OP was just bored and she knew exactly how this thread would play out.

Yeah, I'm going with that last theory.

My cynicism agrees with yours.

You realized that people mean "by volume" when they say that right?

.

See? I weigh the same as I did when I was fat but now my volume is smaller.

Duh - of course you weigh the same in all four picture! A pound of you on any particular date = a pound of you on any other date. Therefore, you always weigh the same. I would have thought that would be obvious.

In fact, everyone on this thread weighs the same as everyone else!

;-)