could be a bearing? were the brakes inspected very closely? it sounds like a feeler tab on a brake pad is just touching the rotor barely. This can happen even though the brakes are say 30% visually estimated remaining. Spin the LF wheel as hard as you can with it up on a jack and see if you can hear the noise. If the noise is in the rotating moving assembly for sure.... That's bearing or brakes! Unless the squeak you are describing is a dry front end part like a ball joint.....Take it to a front end shop if nothing else is found wrong and pay the small diag fee to find out, then get 2 or 3 estimates. Ask about parts warranties too, don't let the cheap price fool you. Some parts are plastic inside and some a brass, lifetime warranty, the best. Also check the thin metal backing plate behind the rotor, it may be touching the rotor as it spins around, it should be about a pinky finger away from the back side of the rotor. Advise if you find more.
friction by applying the brakes? When you apply the brakes, there are pads on either side of the metal part of the wheel, they squeeze together tighter and tighter until the wheel stops turning, which stops the motion of the bike.
use your emergency brake if in motion, if not in motion get new brakes!
Brakes using friction halt or slow down mechanical motion.
Inertia of Motion
have your brakes checked
Strike-slip faults have little vertical motion.
the brakes in your car
try stopping a car without brakes!
Inertia. A body in motion will remain in motion unless acted upon by an outside force. The motion of the bus is stopped by the brakes. The person inside keeps moving as it is not being braked.
Friction
Because friction acts against an object in motion causing it to slow down. Brakes does the same thing.
Strike-slip faults have little vertical motion.