What common device is used for measuring flow rate?

The correct answer is a flow meter. A flow meter is specifically designed to measure the flow rate of liquids or gases within a system. It provides direct readings that are crucial for managing and optimizing various industrial processes, ensuring that operations run efficiently and safely. Flow meters come in several types, including mechanical, electromagnetic, and ultrasonic, each suited for different applications based on the fluid type and flow conditions.

While an orifice plate can also be used to measure flow rate, it is not a standalone device like a flow meter; rather, it is a component that creates a pressure drop in a flowing fluid, which can then be used in conjunction with other devices to determine flow rate. In contrast, flow meters provide direct measurement capabilities and often include additional features for ease of use and interpretation.

The other devices listed play different roles in a system. A pressure gauge measures pressure within a system rather than flow rate, and a flow switch is used to indicate whether flow is present or not, activating or deactivating a circuit based on flow conditions, rather than quantifying the flow rate itself.