Which is heavier? 1lb of lead or 1lb of feathers?

[AbyssalPlains]

The answer lies in the equipment configuration that you used for your 14-foot shore dive. You said you were using "the same suits, ballast of gear, tanks, air, etc. The difference was that instead of using the LDS lead and weight belts, we used our pocket weight belts with weights I pulled from my weighted pull-up vest. They are a pound each and I think they are made out of iron with a glossy black paint. When I weighed them with my luggage scale, they were just over 15 lbs and 12lbs."

What you should have used is a snorkel.

 

[DevonDiver]

On the shore dive, my wife could not descend as she was too buoyant. She tried everything and the only way should could submerge is if I pulled her down with me and then she slowly floated back up.

From my experience as an instructor, the most common problem that novice divers have with descending is incorrect technique, not insufficient weighting. This could explain the discrepency in this instance.

It could be that the BCD was not fully deflated. Not raising the LPI properly, can leave some air remaining.

It could be that your wife did not fully exhale to begin her descent. This is common when there is some apprehension before the dive.

It could be that your wife was instinctively finning or sculling as she tried to descend. Even a small amount of fin movement can provide substantial upwards thrust - which can be mistaken for excess buoyancy.

Lastly, of course, it could be a difference in the stated weights. Some weights are not accurately cast..leading to differences. Some divers mistake lbs for kgs and vice versa.

 

[The Kraken]

"Which is heavier? 1lb of lead or 1lb of feathers?"

1 pound, as set forth by the NIST, is an expession of weight which must comply with a national standard, therefore, regardless of the molecular make up of the material, the weights must be the same . . . the 1 pound standars as set forth by the NIST.

1 Lb. = 1 Lb.

the K

 

[fire_diver]

"Which is heavier? 1lb of lead or 1lb of feathers?"

1 pound, as set forth by the NIST, is an expession of weight which must comply with a national standard, therefore, regardless of the molecular make up of the material, the weights must be the same . . . the 1 pound standars as set forth by the NIST.

1 Lb. = 1 Lb.

the K

1 Lb in air is NOT = 1 Lb in water.

 

[mrmagoo560]

All bets are off when you change the medium you weigh them in. Don't forget the bouyancy factor invloved. One pound of lead and one pound of plastic would have VASTLY different "weight" underwater.

That is true palstic would weigh less underwater,but lead and iron should in theory weigh the same underwater.

 

[Charlie99]

"Which is heavier? 1lb of lead or 1lb of feathers?"

1 pound, as set forth by the NIST, is an expession of weight which must comply with a national standard, therefore, regardless of the molecular make up of the material, the weights must be the same . . . the 1 pound standars as set forth by the NIST.

1 Lb. = 1 Lb.

the K

So which is heavier, a pound of feathers or a pound of gold?

(yes, it IS a trick question).

 

[Charlie99]

.......,but lead and iron should in theory weigh the same underwater.

Mr Magoo, you should put on your glasses and read the post by ss7, above.

 

[The Kraken]

So which is heavier, a pound of feathers or a pound of gold?

(yes, it IS a trick question).

Using the NIST they are the same.

But if you start using the avoirdupois scales, etc. then that's a different matter.

Perhaps I should have been more clear in my statement that one must presume that you are referencing the U.S. Customary unit (which is the Avoirdupous scale) of the pound wich is equivalent to 16 ounces, 7.0000 grains or 453.59237 grams.

So, to which scale do you subscribe?

the K

 

[The Kraken]

Weight is a factor of the pull of gravity.

Take it up with Einstein.

the K

 

[The Kraken]

Do not misconstrue weight with specific gravity.

the K