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E=MC squared? Assuming this is correct which I assume it is, a rechargeable battery should weigh more when charged, compared to un charged, has anybody actually put this to the test?
Not by measuring batteries, but there have been many accurate tests.Originally posted by Devilin
What about a large battery then ? Ok maybe the amount of charge/mass would be to small to measure, but has anybody anywhere actually put this theory to a practical Physical test?
That's a bit high, the highest I could find stored around 1,924,560jOriginally posted by Peter_C
The formula E=MC^2 gives you energy in joules when mass is in kilograms and the speed of light is in meters/second (approx 300*10^6)
Now if I recall correctly some 9V batteries store somwehere around 10 Mj of electrical energy.
Oops. You only divided by c here, not c² like you should have.
we work this out to be 10,000,000=M*C^2
Knowing C is approx 300,000,000 we divide: 10*10^6/300*10^6=0.0333... kg or.. 0.0000333.... grams.
By using the value I found, and dividing by c² we get 2.14 x 10^{-14} grams. A 9v battery masses about 30g so you would need a scale that was accurate to within 1 part in 10^{15}
That is a whopping 3/100,000th's of a gram in one 9v battery...
Not correct, as shown by the following example:Originally posted by Peter_C
One thing I may be forgetting in the above post is that the molecular energy is stored similar to kinetic energy... it is potential energy waiting to be released... For example a compressed spring holds no more mass than the same spring uncompressed.