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: Question about integrals in physics

  1. Oct 21, 2009 #1
    The equation that I have to find Impulse (J) is:

    J = (integral from Ti to Tf) F * dt

    I think dt means difference in time but I'm not sure. Can someone explain to me what dt is and how to calculate it?
  2. jcsd
  3. Oct 21, 2009 #2
    dt refers to an infinitesimal small period of time, there is no 'calculation' of it. Basically, what the above integral is doing is summing up the change in momentum (impulse) at every instant in time, given by F dt, where dt is an infinitesimally small period of time during which the force F can be considered as constant.
    To understand it better I recommend you look at a calculus text.
  4. Oct 21, 2009 #3
    dt means you are integrating with respect to time. So t is the variable and everything else is a constant as far as integration goes.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook