Which sensor is designed to measure the height of water in a tank or reservoir?

• A. Water Level Sensor
• B. Water Quality Sensor
• C. Power Sensor
• D. Wired/Wireless Sensor

Answer: (A)

Measuring how high the water sits in a tank or reservoir requires sensing the water surface level. A water level sensor is specifically designed for that purpose, converting the position of the water surface into a signal that can control pumps, alarms, or shutoffs. There are multiple ways to implement this, such as a float switch that moves with the water, an ultrasonic sensor that pings the surface and measures distance, a hydrostatic pressure sensor that infers depth from pressure, or radar methods that detect distance without contact. The key idea is turning the water’s height into a usable electrical signal for automatic control.

Water quality sensors, in contrast, monitor properties like pH, turbidity, or salinity. Power sensors track electrical power or energy usage. Wired/wireless sensors describe how data is transmitted rather than what is being measured.