ABS - Antilock Braking System, was designed to prevent the wheels of a vehicle from locking up in the event that hard braking was applied. ABS prevents locking up of the brakes in order to enable the driver to steer the vehicle even though that brakes are fully applied.
The way that the wheels are prevented from locking up is that the brake calipers open and close at a very high frequency.
Q1. What is the frequency of the open/close cycle?
Q2. Since the brakes open and close, does that mean that a vehicle with ABS will take a longer distance to come to a stop as compared to another vehicle without ABS? (assuming that the identical vehicles were travelling at the same speed and brakes are applied at the same time/location)