1. Not finding help here? Sign up for a free 30min 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!

Time constant 1/RC

  1. Dec 11, 2007 #1
    where is this equation from?
    what does it equal?
     
  2. jcsd
  3. Dec 11, 2007 #2

    chroot

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Well, presumably you're talking r as an electrical resistance, and c as an electrical capacitance. (Note that people ordinarily use the capital letters R and C for these quantities.) Also, you're not describing an equation, you're describing an expression.

    The expression RC has units of seconds. It is known as the "time constant" of a circuit formed by a resistor and capacitor. Imagine giving this circuit a step input, perhaps from 0V to 1V. The time constant is the length of time needed for the circuit's step response to be within a factor of 1/e of its final value. The factor 1/e is around 37%. Thus, after one time constant, the output voltage is about 63% of its final value.

    - Warren
     
    Last edited: Dec 11, 2007
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Time constant 1/RC
Loading...