On Sunday, June 26, 2016 at 10:23:30 AM UTC-7, tb wrote:
I just purchased an LG 24M38H LED monitor. It comes with a DC power
adapter similar to this one:
http://www.lg.com/us/mobile-accessories/lg-WCP-700TA-wireless-charging-pad

The problem that I am having is that the cable is only approx. 4 ft
long.

It's inefficient and unreliable to extend the DC barrel connector. Just use a two-prong AC extension on
the power brick AC input, instead. Or do what I do, fasten an AC power strip under the table...