Alcohol Sensor:
As the name suggests, an Alcohol Sensor detects alcohol. Usually, alcohol sensors are used in breathalyzer devices, which determine whether a person is drunk or not. Law enforcement personnel uses breathalyzers to catch drunk-and-drive culprits.
Ultrasonic Sensor:
An Ultrasonic Sensor is a non-contact type device that can be used to measure the distance as well as the velocity of an object. An Ultrasonic Sensor works based on the properties of the sound waves with a frequency greater than that of the human audible range
