E=mc2 questions?

[Dywyddyr]

so the mass is always equal to the weight

The mass is "equal" to the weight ONLY under 1G.

for example I have 9.81n I know i have 1kg, I can not see how there is any real difference, to me I see the exact same thing.

One more time: on Earth (under 1G) there isn't any "real difference".
Elsewhere the difference is CRITICAL.
That's why physics (and the equations thereof) use MASS and not weight. Otherwise those equations wouldn't have the applicability that they do - they'd have to be adjusted for different locations/ conditions.

 

[Russ_Watters]

Not quite.
lb is mass. lbf is force.

No: you can say lbf or lbm, but if you omit the last letter, it means force:

http://en.m.wikipedia.org/wiki/Pound_(force)

 

[theorist-constant12345]

Not quite.
lb is mass. lbf is force.

No, you actually are telling untruths, as you have been doing continually in this and many other threads. It's that simple.

If an object x has an energy constant , an equilibrium of energy E=mc2, the total energy contained in that system, if a force is applied on that system then it either gains or loses PE , has shown in Kinetic energy such has a falling object, 9.81m/s2, force increasing over altitude that will hit the ground.
A stationary object on the ground, loses energy to the constant force of gravity, you can see this with your caesium clock atom and the corresponding beats, at altitude you can see the output difference by less interference of gravity.
The object on the ground that should be a state of equilibrium of E=mc2 is always at a loss to gravity, so E=mc2-G = entropy loss to entropy gain, something along those lines, I am trying to help and to show you about the Poles , Ice = E=mc2-E/G

gravity makes the ice, by maintaining an energy loss of the water, but the atmosphere is now allowing by entropy means the ice to gain energy greater than the loss of energy to G.

 

[Russ_Watters]

I get this, but the part im trying to express is that you have mass as kg etc, and in the normal world this is weight that is measured by the force applied by gravity of an object on a set of scales, so the mass is always equal to the weight, for example I have 9.81n I know i have 1kg, I can not see how there is any real difference, to me I see the exact same thing.

If you try to push a car, you can see the difference. You use a=f/m to accelerate the car and you aren't acting against gravity.

Or, consider in space with no gravity and therefore no weight: do you thinkvit is just as easy to move around the Hubble Space Telescope (which has about the size and mass of a bus) as bit is for the astronaut to haul around his toolbox?

 

[Russ_Watters]

If an object x has an energy constant , an equilibrium of energy E=mc2, the total energy contained in that system, if a force is applied on that system then it either gains or loses PE , has shown in Kinetic energy such has a falling object, 9.81m/s2, force increasing over altitude that will hit the ground.

You need to stop trying to sound smart and instead start learning physics from scratch. All you are doing here is generating meaningless gibberish.

I mean, how am I supposed to explain the equivalence of mass and energy to a person who has no idea what mass and energy are?... And belligerently wants to stay that way?

 

[paddoboy]

If an object x has an energy constant , an equilibrium of energy E=mc2, the total energy contained in that system, if a force is applied on that system then it either gains or loses PE , has shown in Kinetic energy such has a falling object, 9.81m/s2, force increasing over altitude that will hit the ground.
A stationary object on the ground, loses energy to the constant force of gravity, you can see this with your caesium clock atom and the corresponding beats, at altitude you can see the output difference by less interference of gravity.
The object on the ground that should be a state of equilibrium of E=mc2 is always at a loss to gravity, so E=mc2-G = entropy loss to entropy gain, something along those lines, I am trying to help and to show you about the Poles , Ice = E=mc2-E/G

gravity makes the ice, by maintaining an energy loss of the water, but the atmosphere is now allowing by entropy means the ice to gain energy greater than the loss of energy to G.

What has all this to do with weight and mass?
Are you once again trying to create diversionary tactics?
Do you now accept the first year basic physics "axiom" that weight is not the same as mass?

 

[AlexG]

Again I ask again E=mc2, what is the effect of gravity in this equation?

Gravity has no effect on the equation. Gravity plays no role because weight and mass are not the same thing. You were told that before.

 

[brucep]

This is my confusion, if i go the shop and ask for 1kg of apples, the shop assistance weighs them out, and 1kg is the weight, this is something people of earth observe.

So you are now saying that everyones life is lie, because you are not weighing the apples you are measuring their mass?

http://physics.info/weight/

So weight isn't the same as mass. Get it?

 

[Kittamaru]

Okay, this is... quite the farce.

Mass is mass, regardless of the effect of gravity acting upon it.

WEIGHT is the effect of gravity (or other inertial force) upon that mass.

Ergo:

A bowling ball with 100kg mass, will weigh 100kg in a 1g environment.

Take that same bowling ball to a 0g environment, it will STILL HAVE 100kg of mass, but will weigh, effectively, nothing (at least whilst at rest).

Technically speaking, something such as a scale SHOULD measure in Newtons... but that would confuse people. That, and a scale can be fooled.

Go stand on your scale at home - it will show your "weight". Now, GENTLY, jump up and down on it - you will see your "weight" change, even though your mass stays the same.

This is because you are adding inertia into the mix.


theorist-constant12345, this has been explained to you several times over now... and you seem bound and determined NOT to accept/understand it... what is your explanation for this?

 

[Russ_Watters]

I get this, but the part im trying to express is that you have mass as kg etc, and in the normal world this is weight that is measured by the force applied by gravity of an object on a set of scales, so the mass is always equal to the weight, for example I have 9.81n I know i have 1kg, I can not see how there is any real difference, to me I see the exact same thing.

"In the normal world" is only for bathroom scales and people who know NOTHING WHATSOEVER about physics. Literally: the first equation most people learn is f=ma, which tells you how they are different/related.

 

[theorist-constant12345]

Okay, this is... quite the farce.

Mass is mass, regardless of the effect of gravity acting upon it.

WEIGHT is the effect of gravity (or other inertial force) upon that mass.

Ergo:

A bowling ball with 100kg mass, will weigh 100kg in a 1g environment.

Take that same bowling ball to a 0g environment, it will STILL HAVE 100kg of mass, but will weigh, effectively, nothing (at least whilst at rest).

Technically speaking, something such as a scale SHOULD measure in Newtons... but that would confuse people. That, and a scale can be fooled.

Go stand on your scale at home - it will show your "weight". Now, GENTLY, jump up and down on it - you will see your "weight" change, even though your mass stays the same.

This is because you are adding inertia into the mix.


theorist-constant12345, this has been explained to you several times over now... and you seem bound and determined NOT to accept/understand it... what is your explanation for this?

I can not get it to make sense even with the explanations it sounds contradictory, even your own example sounds to say the same thing .

''A bowling ball with 100kg mass, will weigh 100kg in a 1g environment.''


So the bowling ball has the same mass has weight being the same thing?


Kg is weight measurement so how does the mass kg differ from the weight kg?

It reads the same to me.

 

[Dywyddyr]

I am trying to help and to show you about the Poles , Ice = E=mc2-E/G
gravity makes the ice, by maintaining an energy loss of the water, but the atmosphere is now allowing by entropy means the ice to gain energy greater than the loss of energy to G.

Total and utter bullshit.

 

[Russ_Watters]

The mass is "equal" to the weight ONLY under 1G.

That's confusing too: MA's is never equal to weight: one is force and one is an "amount of matter". They are different quantities with different units. It is better IMO to say you can use a pre-calibrated scale to read "mass", but what it is actually doing is measuring weight, then converting to mass by assuming it is on the surface of earth.

 

[Kittamaru]

I can not get it to make sense even with the explanations it sounds contradictory, even your own example sounds to say the same thing .

''A bowling ball with 100kg mass, will weigh 100kg in a 1g environment.''


So the bowling ball has the same mass has weight being the same thing?


Kg is weight measurement so how does the mass kg differ from the weight kg?

It reads the same to me.

That's the thing Mass =/= Weight...

Do you understand Mass, Volume, and Density? For example, what weighs more:

A 5 foot cube made of straw, or a 4 foot cube made of lead?

Obviously, the 5 foot cube is "bigger"... however, the 4 foot cube of lead weighs more.

This is because, despite having a smaller volume, the lead is much more dense; it has more physical mass in a smaller space than the straw, thus the force of gravity (which is a constant acceleration) makes it exert more force.

What I will say, theorist, is that if you truly have such an issue with this concept (which is, honestly, a very basic and fundamental concept in the grand scheme of things), you may want to stop thinking in terms of "what you can accept" and more in terms of "what you are being told"... otherwise, your discussion is going to go exactly nowhere.

 

[Dywyddyr]

That's confusing too: MA's is never equal to weight: one is force and one is an "amount of matter". They are different quantities with different units. It is better IMO to say you can use a pre-calibrated scale to read "mass", but what it is actually doing is measuring weight, then converting to mass by assuming it is on the surface of earth.

I did, deliberately, put "equal" in quotes. I thought that it would better suit TC's level of comprehension.

 

[Russ_Watters]

By the way, in this "real world" where people know NOTHING WHATSOEVER about physics, people do actually refer to a "kilograms force": http://en.m.wikipedia.org/wiki/Kilogram-force

 

[Russ_Watters]

I did, deliberately, put "equal" in quotes. I thought that it would better suit TC's level of comprehension.

Fair enough: I doubt he'd get that level of subtlety. I didn't and I actually know you know what you are talking about!

 

[AlexG]

E = mc^2 gives the energy equivalent of a given MASS m. You are hung up by the fact that in everyday language, weight and mass are used interchangeably. But that is not strictly the case, it's only the common usage. Terms in science often have more precise meanings than dictionaries give.

 

[theorist-constant12345]

That's the thing Mass =/= Weight...

Do you understand Mass, Volume, and Density? For example, what weighs more:

A 5 foot cube made of straw, or a 4 foot cube made of lead?

Obviously, the 5 foot cube is "bigger"... however, the 4 foot cube of lead weighs more.

This is because, despite having a smaller volume, the lead is much more dense; it has more physical mass in a smaller space than the straw, thus the force of gravity (which is a constant acceleration) makes it exert more force.

What I will say, theorist, is that if you truly have such an issue with this concept (which is, honestly, a very basic and fundamental concept in the grand scheme of things), you may want to stop thinking in terms of "what you can accept" and more in terms of "what you are being told"... otherwise, your discussion is going to go exactly nowhere.

Thank you for the great post, and yes I understand the density mass function, a kg of feathers will have a greater volume of spacial room than a kg of gold, the gold having a much greater density per cm3 than the feathers,

I understand your definition of mass and weight been two different things, and it is trivial that I see it has one and the same, E=mc2 was my aim of debate and not really an argument about weight and mass although the subject does cross E=mc2 in what i am asking.

I see water at an equilibrium of E=mc2 per cm3, and by entropy means of greater loss of energy to gravity turns into ice, and by entropy means replaces the loss to return to water.


Is this possible what i suggest?

Please ask if you do not understand what i am asking and i will try to write it better.

 

[theorist-constant12345]

E = mc^2 gives the energy equivalent of a given MASS m. You are hung up by the fact that in everyday language, weight and mass are used interchangeably. But that is not strictly the case, it's only the common usage. Terms in science often have more precise meanings than dictionaries give.

Thank you ok, I understand now why you separate , in every day it is different, now you have answered the why's, thank you.