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I am interested in knowing how much is one eV of energy. Everywhere I found are the technical definitions. Can anybody please tell me how much is this much energy. I need something which I can feel. I mean how much work I can do with 1 eV? Can I drive a 1000cc car for 1hour? Any of example in context of real life usage would be interesting.

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up vote 9 down vote accepted

An electron volt is just the energy acquired when an electron of charge $e$ falls through a potential of 1 volt, which means $$1eV = e \times 1 = 1.6 \times 10^{-19} J$$

When you lift up your $2.5Kg$ laptop (a 15-inch apple macbook pro, for example) by a foot, you do a work of approximately $2.5 Kg \times 10 ms^{-2} \times 0.3 m = 7.5 J$ which is about $4.7 \times 10^{19} eV$. So an $eV$ is a really low energy scale by everyday standards.

One TeV (a tera electron volt) is about the energy of motion of a flying mosquito.

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In CERN in running LHC project, the scientists say that they are going to do a collision of 8 TeV. So whats the big deal in that? I may be understanding something wrong. Please clear my concept.... –  Surjya Narayana Padhi Apr 5 '12 at 13:11
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A subatomic particle is much, much lighter than a mosquito. In a back-of-the-envelope calculation, let's say a mosquito is 1.7 grams and a proton is 1.7 $\times 10^{-27}$ kg. So to have the same kinetic energy as a flying mosquito, the proton must be travelling about $10^{12}$ times faster than the mosquito. That's a big deal. –  ptomato Apr 5 '12 at 13:32
    
thanks a lot for sharing your knowledge. –  Surjya Narayana Padhi Apr 5 '12 at 14:02
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Also in LHC they are running around 100 trillion protons, each having 8 TeV. The 100 trillion protons weight about 1 nanogram in total (that is like nothing), but their net kinetic energy is huge: it is like a 300 tones train going at 100 km per hour. Imagine that something weighting 1 nanogram has an energy of a fast going train. That puts things into perspective. –  mpv Dec 5 '13 at 0:04
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protected by Qmechanic Dec 4 '13 at 21:56

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