Unraveling the Mystery of e=mc2: How Much Mater is Needed?

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    E=mc2 Mystery
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SUMMARY

The forum discussion centers on the application of Einstein's equation, E=mc², to understand the relationship between energy (E), mass (m), and the speed of light (c). Participants clarify that energy is measured in joules, mass in kilograms, and the speed of light in meters per second. A specific example is provided, where 1 kg of mass equates to approximately 89.8 petajoules of energy. The conversation also touches on the implications of mass-energy conversion, particularly in fictional contexts like Star Trek, emphasizing that mass must be assembled in its original form after conversion.

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  • Understanding of Einstein's mass-energy equivalence formula E=mc²
  • Knowledge of units of measurement: joules, kilograms, and meters per second
  • Familiarity with basic physics concepts, including energy and mass
  • Awareness of the fictional portrayal of mass-energy conversion in media
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  • Research the implications of E=mc² in nuclear physics
  • Explore the concept of mass-energy equivalence in practical applications
  • Learn about the speed of light and its significance in physics
  • Investigate the differences between mass and energy in quantum mechanics
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Students of physics, educators, science enthusiasts, and anyone interested in the principles of energy and mass conversion as described by Einstein's theory.

Grimstone
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e=energy
m=mater
c=speed of light
Squared.

i am not one of you. I am a simple joe.
so.
energy =mater times the speed of light. Times the speed of light. ?
or
energy=mater times (ℂ time ℂ) ? (aprox 36 trillion)Next question.
If we know the formula, what are the measurements? are we talking pound of iron?
or one atom of iron?
are we talking one Wat or one mega-gigawatt's?
How much mater are we talking about?
Assuming one was to beam Capt Picard and he weighs 170 pounds.
we need to know if the formula is per atom of pound of baldness.
Please, KIS,IS keep it simple, I am stupid.
 
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Grimstone said:
e=energy
m=mater
c=speed of light
Squared.

i am not one of you. I am a simple joe.
so.
energy =mater times the speed of light. Times the speed of light. ?
or
energy=mater times (ℂ time ℂ) ?

The two are equal.

Next question.
If we know the formula, what are the measurements? are we talking pound of iron?
or one atom of iron?

It doesn't matter. That's the point of this formula, we can apply it to a mass of any size.
 
Ok. it does matter.
if we are talking
1 wat per pound.
or
1gigawat per atom.
 
Grimstone said:
Ok. it does matter.
if we are talking
1 wat per pound.
or
1gigawat per atom.
Consider it this way:

E = energy in joules
M = mass in kilograms
C = speed of light in metres per second

So if you had 1kg that would be:

E = 1 * 2997924582

Which is:

8.98755E+16 Joules

So 1 kg of mass represents 89.8Petajoules of energy (peta = 1*1015)

FYI a watt is a joule per second. So 1 gigawatt would be 1 billion joules per second (giga = 1*10^9)
 
By comparison the US average electricity output is about 1.6 E+15 J/hr
 
Ryan_m_b said:
Consider it this way:

E = energy in joules
M = mass in kilograms
C = speed of light in metres per second

This is what I was looking for. thank you.
on a side note.

I thought ℂ= 186,k miles per sec.
 
Grimstone said:
This is what I was looking for. thank you.
on a side note.

I thought ℂ= 186,k miles per sec.
C is the speed of light, it can be expressed in any unit of distance over any unit of time but for the same of e=mc2 if you're going to use SI units then use metres per second.
 
Not that I can. but.
at 175 pounds. or 79.37
E=2,745,884,520,000 Joules needed to form
M 79.37

we are skipping the facts that it would have to be put together in a sequence to that of a DNA strand.

thank you for helping me understand the formula. PF mentor.
 
Grimstone said:
Not that I can. but.
at 175 pounds. or 79.37
E=2,745,884,520,000 Joules needed to form
M 79.37
I don't understand what you mean here. 175lb = ~79.37kg but that equates to 7.14e18J.
Grimstone said:
we are skipping the facts that it would have to be put together in a sequence to that of a DNA strand.
This sentence makes no sense :confused:
Grimstone said:
thank you for helping me understand the formula. PF mentor.
No worries but given this post I'm not sure you understand yet.
 
Last edited:
  • #10
Hi.

Consider this:

Body is standing still. Just chilling.

Then this still body emits two identical photons of light, both at the same moment: one to the left, and one to the right.

Photons are on their way now, away from body, carrying energy. Both photons are same, they are identical. They carry same amount of energy. So - body is still still.

Photons carry energy away. So body must have lost this energy. Energy was taken from body and is now going away, photons carry it away. Thus, body lost some energy.

But: what is this lost energy? Body is still. Body was still. What did body lose then?

You can say body lost mass - what else is there body could lose?. Like, when You and Your friend are on a boat, on a river, and You both throw away two identical balls, at the same time, to the left and to the right. Balls have mass, right? So You and Your boat lost some mass -- mass of two balls. But: photons don't have rest mass! They just have energy and move at speed of light! So, body lost mass, which is actually energy moving with speed of light :smile:

When all the numbers are put together one finds E = m c^2. Two photons have energy E both together, and body lost mass m. Speed of light is c.

Simple enough, right? I hope this helps a bit.

Cheers.
 
  • #11
175 is the weight in pounds. the converter says 79.3 Kg. took that times C times C and got 2,745,884,520,000.
As the reply said that the unit is Kg for mass and Joules for E then it would take 2,745,884,520,000 joules of power to create that 175 pounds. but in transportation (beaming) you would still need to assemble the mass in the original form.

All I really wanted was to know what measurements the E and M are.
 
  • #12
Grimstone said:
175 is the weight in pounds. the converter says 79.3 Kg. took that times C times C and got 2,745,884,520,000.
As the reply said that the unit is Kg for mass and Joules for E then it would take 2,745,884,520,000 joules of power to create that 175 pounds. but in transportation (beaming) you would still need to assemble the mass in the original form.

All I really wanted was to know what measurements the E and M are.
You have to times the mass in kilograms by the speed of light squared. The gives you the energy. So;

E = 79.3 * 2,745,884,520,000

Also it's worth pointing out that star trek transportation is nothing more than fiction. If you magically converted the mass of a person to energy you wouldn't get a beam-me-up moment, you'd get a massive explosion.
 
  • #13
I am aware that trek beaming is fiction. but i did not know what the units was. be it per Kg or per atom.
 

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