1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Current and voltage

  1. Jan 22, 2012 #1
    1. How could I test for faults in a circuit using a continuity tester containing a light and a battery?

    2. If three lamps are rated 6v and 0.05A, what size of current will be drawn from the battery. Explain why this is. (Series circuit)

    3. If three lamps are rated 6v and 0.05A, what size voltage must the battery be to allow them to operate properly? (Parallel circuit)

    This is me trying to answer the questions. :D :

    1. Would you just connect the "X" and "Y" wires to something for it to be tested?

    2. I don't really get this one at all. Would it be 0.15A because there's three lamps and it's in a series circuit? How would I explain it though?

    3. Since it's a parallel circuit and not a series, would the battery just have to be 6v? I know why, but I just don't know how to explain it, please help. :D

    Edit : Also, is this a continuity tester using a bulb and a battery? :

  2. jcsd
  3. Jan 22, 2012 #2
    Why are people not helping me out?

    I think this should be a pretty easy question to figure out for some of you.
  4. Jan 22, 2012 #3


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    Hello Kyleee. Welcome to PF!
    Have some patience.

    While you're waiting read to rules for this Forum. Please don't post the same question in more than one thread.
  5. Jan 22, 2012 #4
    I didn't mean that, I don't even know how it happened. :P
  6. Jan 22, 2012 #5


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    For #1:
    I don't see any X or Y wires in the figure.

    Should you disconnect whatever you're testing from its power source before testing?​
    For #2:
    What voltage is used for the combination of the three light bulbs?

    What is true of any current coming from the battery and then passing through the first bulb? Does it pass through any other bulbs before returning to the battery?​

    For #3:
    Yes, but it would be a good idea for you to try to explain it.​
  7. Jan 22, 2012 #6
    Yes, it passes through 3 bulbs. All three bulbs are rated 0.05A, 6v.

    I've figured out the rest of the questions myself, this is the last one I've got to do. Then, after I've done my physics homework, I've got to go and study for a maths and geography test tomorrow, do 3 pages of french and write a bit of an essay and it's already 8:30pm.
    *Face palm* Life is hard.
  8. Jan 22, 2012 #7


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Education Advisor

    What does the 0.05 A, 6V rating tell you about the bulb?
  9. Jan 22, 2012 #8
    It tells you that it's rated at a 0.05 current and 6 volts. I don't understand.
  10. Jan 22, 2012 #9


    User Avatar

    Staff: Mentor

    From this, can you determine the resistance of an individual bulb?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook