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V =IR question

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    The resistance of R2 is 6/3 =2 right? (the answer for this was blank so couldn't check)
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    Yes - A is at 12v and B is at 6v so there must be 12-6 = 6v across R2
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    (Original post by teachercol)
    Yes - A is at 12v and B is at 6v so there must be 12-6 = 6v across R2
    I just looked at the diagram again and got slightly confused.. Why is the PD across A and B different? Isn't the voltage in a parallel circuit equal in each of the branches? So shouldn't the PD across A = PD across B ?
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    (Original post by sabre2th1)
    I just looked at the diagram again and got slightly confused.. Why is the PD across A and B different? Isn't the voltage in a parallel circuit equal in each of the branches? So shouldn't the PD across A = PD across B ?
    Yes, the PD across both branches in a parallel circuit is the same. However, in the second branch, the lamp is in series with R2. So the voltage splits between the two, giving you 6V across the lamp, and 12-6, that is 6V across R2.
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    (Original post by sn8595)
    Yes, the PD across both branches in a parallel circuit is the same. However, in the second branch, the lamp is in series with R2. So the voltage splits between the two, giving you 6V across the lamp, and 12-6, that is 6V across R2.
    Thanks
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    (Original post by sabre2th1)
    Thanks
    Pleasure.

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Updated: April 18, 2012
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