Which physics course takes less time to complete?
I am not sure what level of physics you would like to know about, so this is going to be a bit of a vague answer.
What I can suggest is that you go to this link, online physics programs.
Now, as for the length of time, that is dependent on how much education you have completed thus far. You will need to take a close look at the online physics programs that are offered, and determine which one will best suit you educational goals.
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