You can wire the refrigerator on a dedicated 15 amp circuit using AWG #14 wire but, know that as of 2014 the refrigerator must be on a GFCI protected circuit that is readily accessible. As you will normally mount the outlet behind the refrigerator you would have to move the unit to reset the breaker if and when it tripped. I would wire the refrigerator on one of the 20 amp kitchen counter-top circuits that is GFCI protected. Now, my answer may be debatable but from how I read the NEC code you can wire it to one of the kitchen branch circuits as long as the refrigerator does not pull more than 16 amps. You might want to check with your local inspector to get his opinion as he is the one who will have the final say.
16-gauge wire has a diameter of 0.05082 inches.
AWG # 12 is 2.053 mm in diameter.
12mm
The current capacity varies depending on the length and diameter of the wire
Not unless the wire going to the refrigerator outlet is AWG 10/2. If it is wired with 12/2 wire then you must use a 20 amp breaker. Using a 30 amp breaker is dangerous and a fire hazard.
If the length of the wire increases its diameter decreases
16-gauge wire has a diameter of 0.05082 inches.
There isn't a specific diameter. The thicker the wire the more current it can convey. This diameter will be part of your calculations for your circuit.
large diameter wire simply because it will move easier Technically they would have the same resistance, but the larger diameter wire would allow more current to flow as it would have more room to move.
No, a smaller diameter wire has a higher resistance. The 0.01 mm wire will have 1/100 the cross-sectional area of the 0.1 mm diameter wire, therefore the resistance will be 100 times as high.
The larger the wire gauge, the smaller the diameter. 12 gauge is bigger than 14 gauge.
12 gauge
gauge
By the diameter of the wire.
aprox 10% of the diameter of the wire
22 AWG has a diameter of 0.0253 inch.
Over the same distance the larger diameter wire will have less resistance that the smaller diameter wire.