Chem

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Energy needed to keep a 75w bulb burning for 1 hour = 270kj Calculate energy neede to keep it burning for 3 hours?
In J and kcal?
I got the J: It is 270kj x 1000/1 x 3/1 = 810000=8.1 x 10^5J
But How Do I get the kcal?
Thank you

  • Chem -

    1 cal = 4.184 J
    1000 cal = 1 kcal.

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