Question 124Gas Turbine - Assistant Engineer

The correct answer is A) Voltage is produced when a ferrous material moves through a magnetic field. This is the principle that a magnetic speed sensor/pickup operates on. When a ferrous material, such as a gear or pulley, moves through a magnetic field, it induces a voltage in the sensor. This voltage can be measured and used to determine the speed of rotation. This principle is known as electromagnetic induction and is the basis for how magnetic speed sensors function. The other options are incorrect because: B) Vibration is not the principle behind magnetic speed sensors, C) Force is not directly related to how a magnetic speed sensor works, and D) Variations in the earth's magnetic field are not the mechanism behind magnetic speed sensors.