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Physics (help appreciated)

  1. Mar 14, 2007 #1
    A current of 0.3 A is passed through a lamp for 2 minutes using a 6 V power supply. The electrical energy dissipated by this lamp during the two minutes is:
    a) 1.8 J
    b) 12 J
    c) 20J
    d) 36 J
    e) 216 J

    If someone could just help me to start off that would be great.
    The main equations I have to use are

    E= QV

    (.3A)= (Q)/(120)
    Q= 36

    E= (36)(6V)
    E=216 J

    Am I right:confused:
  2. jcsd
  3. Mar 14, 2007 #2
    looks good, tho ordinarily the power/heat would first be calculated as I*V, then multiplied by 120
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