Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Transformers problem help

  1. Aug 13, 2006 #1
    Please can someone help me with his question

    A transformer has a 120-turn primary winding and an 1800-turn secondary winding. A current of 10A flows in the primary winding when the potential difference of 550V is placed across it. Find the current in the secondary winding and the potential difference across it.

    thank you
  2. jcsd
  3. Aug 13, 2006 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Where would you start with this?

    It's a pretty basic conservation of energy problem once you know where to go
  4. Aug 13, 2006 #3
    so far i have

    120 = 550 =
    1800 33 10

    i got the 33 through the ration of 120/800
  5. Aug 13, 2006 #4
    P=IV in primary coil


    hence 5500W in secondary coil

    pd across secondary coil = 550/120 x 1800 = 8250V

    current across secondary coil = 5500/8250 = 0.67A (2sf)
  6. Aug 13, 2006 #5
    thank you :)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook