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: Specific Charge AS Level HELP?

  1. Apr 25, 2008 #1
    Specific Charge AS Level HELP!?!?!!

    Hi, RIGHT, I am in desperate need of help I am attempting to teach myself Specifiction A AQA AS Physics and need help with how to figure out the specific charge of a nucleus when the charge and mass are not stated.
    It is hard to explain without diagrams but if a nuclus is given, for example C with a small 12 on top and a small 6 on the bottom how would you work out the specific charge for this because my textbook says that you can only work out specific charge if you have the charge and the mass? Hope this makes a vague amount of sense and I may be being very silly but i need someone to explain this to me at a very basic level!!!
  2. jcsd
  3. Apr 25, 2008 #2


    User Avatar
    Homework Helper

    "Specific charge" is the ratio of charge to mass for the nucleus (apparently expressed in coulombs/kg). What do the '12' and the '6' represent in the symbol for carbon-12 that you are describing?
  4. Apr 26, 2008 #3
    Um they are the number of protens and neutrons (the number on top) and the number of protons (number on bottom) This is very basic AS Level Physics just dont know how to work out the specific charge from those two numbers!!
  5. Apr 26, 2008 #4


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Well, using those two numbers you can work out the charge of the nucleus, what is the charge of a proton and a neutron? You can also work out the mass of the nucleus.
  6. Apr 26, 2008 #5


    User Avatar
    Homework Helper

    All right, so what is the charge of the nucleus (what does the '6' also stand for)? You will want to convert that amount of charge into units of Coulombs.

    If the number of protons and neutrons is 12, what is the mass of the nucleus? You will ultimately want to convert that into units of kilograms.

    The specific charge is the ratio of the charge in Coulombs to the mass in kilograms.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook