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Playing with E=MC^2

  1. Jan 28, 2014 #1
    Hi all,

    I've been teaching myself about energy unit conversions (because I never paid attention at school) and just wondered if someone could check my math please? It's not a homework question - I've not been to school for 10 years! Just a curiosity on my part...

    I was trying to work out how much energy is contained in the atoms of household objects and compare it to other things.

    If we compare it to my humble pet parrot, for instance, he weighs 145g.

    So I imagine 0.145kg * 299,792,458 * 299,792,458 = 13,031,950,091,683,900 Joules.

    My house consumes (electric and gas combined) 12,360 kWh of energy in a year.
    If 1 kWh == 3,600,000 Joules then our house consumes:
    3,600,000 Joules * 12,360 kWh = 44,496,000,000 Joules

    So if 13,031,950,091,683,900 Joules / 44,496,000,000 Joules = 292,879...
    ... then the energy wrapped up in Charlie's birdy atoms could power my house for 292,879 years?

    Then if the power consumption of the planet at any one moment is estimated at 15 Terawatts, or 15,000,000,000 kW, and 1 kW is 1,000 Joules/Second then the earth's consumption is:
    15,000,000,000 kW * 1,000 Joules/Second/kW = 15,000,000,000,000 Joules/Second.

    Then my birdy, suitably atomised and exploded beyond all recognition, could power the entire earth for:

    13,031,950,091,683,900 Joules/bird / 15,000,000,000,000 Joules/Second = 868.8 seconds/bird.
    868.8 seconds / 60 seconds/minute = 14.48 minutes.

    So, if his atoms weren't so stable, my bird could power the entire earth for 14 minutes.

    Am I right, or has my maths gone horribly awry? :shy:
  2. jcsd
  3. Jan 28, 2014 #2
    Well I think the math is ok, but how much energy do you think it would require to "exploid" the energy contained within Charlie in the manner you suggest is possible?
  4. Jan 28, 2014 #3
    Lol, probably a lot more than you'd get out of it, I should imagine! Which is why I keep Charlie as my pet, instead of using him to power the world. Noble as that would be, of course. :P

    Thanks for your reply my friend.
  5. Jan 28, 2014 #4
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