Understanding Dimensional Analysis: Solving for i, j, and k Values

1 reply · 2K views · last reply
dexstarr
Messages
4
Reaction score
0
I'm having trouble understanding a step. How are the values of " i , j , and k " derived? When equating the powers what step has to be done? I have been stumped on this for a while and I think I'm just over thinking it.

https://www.dropbox.com/s/agc0ga9hsjd04jn/Sample%20Problem.png
 
Attachments
  • Printed textbook text reading Sample Problem 1-5: the Planck time from the speed of light c, Newton's gravitational constant G, and Planck's constant h, to be found by dimensional analysis.
    Sample Problem.png
    19.7 KB · Views: 154
What they have done is to use the fact that the fundamental quantities of length and mass must have exponents of zero, since we wish only to have a unit of time left, with an exponent of 1. So this gives us 3 equations in 3 unknowns.