Head phone jack

If we insert a 2 conductor mono(one side) earplug in to a stereo output jack, then it will short one of the amplifier channel, am I right? Just wanted to confirm this danger scenario

Heh, adding a same line of question, can I use a regular 3.5mm stereo headphone with a 4 conductor, 3.5mm mobilephone jack to listen audio? It will be shorting at least the mic receptor right? Or why they're advertising that 3.5mm audio jack provided, if it is not possible then

Most kit has series resistors and/or capacitors in the input/output circuits to prevent damage from a short or low resistance at the jack.

What it will do is open the connection to the speakers (or output amplifier, depending upon how the jack is inserted into the circuitry) and the barrell of the plug will short the output of the left and right channels together. As mentioned, there is likely enough source resistance that there will be no ill effects. If you can set your stereo to monophonic operation with mono headphone operation, you'll definitely lower the chances of problems as both channels will be carrying the same program material.