CPFT Practice Exam 2025 – Complete Test Prep Guide

The infrared analyzer utilizes a chopper motor as a key component in its functioning. This device is designed to measure the concentration of gases by detecting the absorption of infrared light at specific wavelengths. In the infrared analyzer, the chopper motor interrupts the infrared beam in a controlled manner, alternating the signal that reaches the detector. This modulation allows the system to differentiate between the light transmitted through the sample and the background, enhancing the sensitivity and accuracy of the readings.

The other devices mentioned do not rely on a chopper motor for their primary functions. Blood gas analyzers focus on measuring gases dissolved in blood without the need for modulating light. Rotameters operate on the principle of float position in a tapered tube to measure gas flow rates, while barometers measure atmospheric pressure without necessitating a chopper mechanism. Understanding the unique functionalities of these devices helps clarify why the infrared analyzer stands out in this context as the one that incorporates a chopper motor.