How do you know the mechanical watches or quartz watches in first glance?

That is really a good question. if you take the watch in hand, there are several ways to know it in mechanical or quartz, weight, See-through Caseback of watch, imprint on Watch Dial for "AUTOMATIC" or QUARTZ", Wind the Watch Crown, shaking the watch slightly to feel the interior of movement moving and so on. But if you were in a party, business meeting, social activity, He or She wear the watch in his/her wrist. How do you know it in first glanze instead of taking the watch to evaluate? There is A easy way to see if the second hand of movement is sweeping/gliding or jumping/ticking. pls see below photo.

watch-movement second hand difference

Mechanical sweeping second hand Quartz Jumping second hand

this photo quoted from www.wixonjewelers.com

If sweeping, it is Mechanical watch, if Jumping, it is quartz. of course if you have both watches, Put them together to see the second hand motion. this is quite interesting. like first time i know it. my reaction is Wooo. so easy. isn't it?
Yes, this difference is bcs of the movement working different systems. Mechanical movement likes a autonomous machine to give the power by gears and springs, the mainspring store and release the engery/power to turn the Watch Hands and power other complications. actually the sweeping second hand means the hand moving in a fast rate due to the interior mechanical movement. this system use Balance wheel and escapment to track time actually minimal 6-8times moving per second and it directly connected to second hand, this is why the second hand in beautiful sweeping motion. the quartz movement powered by battery. the most quartz movements set the second hand in jumpier every second to save the engergy. few high end luxury brands develop the sweeping second hands for Quartze watch too. 95% quartz watch in Jumping second hand.