# Phase front of a quantity e^jwt

## Homework Statement

This is a statement i found in one of my textbook of "Antenna analysis".

The phase front of a exponential time varying quantity(charge distribution) 'ejwt' is a spherical wave front and is represented by e-jkR.

## Homework Equations

1. How can we represent spherical wavefront as e-jkR for a quantity exponential time variation ejwt ?
2. Does the term wt have a physical meaning?

## The Attempt at a Solution

Please look into my attempt from the beginning and correct me if I am wrong anywhere.

Consider a complex quantity ejwt = cos wt + j sin wt.
Re{ejwt} = cos wt
Im{ejwt} = sin wt

Now, if we plot this quantity with one axis as real axis i.e., cos wt and other axis as imaginary axis i.e., sin wt. Then we obtain a circle for different values of wt.

Is this the circle we that is the constant phase spherical wavefront of ejwt. But in this circle actually the phase wt does vary which is how we obtain the circle.
How do we relate this circle to e-jkR?

Related Engineering and Comp Sci Homework Help News on Phys.org
blue_leaf77