- #1

Pushoam

- 962

- 52

## Homework Statement

We have ## f(x,t) = cos(kx - \omega t)

\\ g(x,t) = cos(kx - \omega t + \epsilon ) ##

How to find out whether f lags behind g or vice -versa?

## Homework Equations

## The Attempt at a Solution

I took, x =0,

g (t') = f(t)

## - \omega t' + \epsilon = - \omega t ##

## t' = t + \frac { \epsilon }{\omega} ##

If ## \epsilon ## > 0, then t'> t, thus g lags behind f.

And if ## \epsilon < 0 ## , then t'<t , thus f lags behind g.

Is this correct?

Or is there any other way to find quickly just by seeing the functions?