Voltage is converted into what in the sensor?

• A. Light
• B. Heat
• C. Magnetic field
• D. Digital signal

Answer: (D)

The basic process here is analog-to-digital conversion. A sensor often turns the physical quantity it measures into an electrical voltage that represents the value. To use that information with digital electronics, that voltage is converted into a digital signal by an analog-to-digital converter. The ADC samples the voltage at intervals and encodes it as binary data, with a certain resolution and sampling rate, so the system can process, store, or transmit the information reliably.

Light, heat, and magnetic field describe other aspects (the physical output the sensor might detect, or other forms of data), but the conversion described in the question ends with a digital signal—the digital representation of the measured quantity.