Which device is specifically designed to measure the surface temperature of an object?

The device specifically designed to measure the surface temperature of an object is the pyrometer. Pyrometers are particularly useful for measuring high temperatures and are often used in applications where direct contact is not possible or where the object being measured is very hot.

Pyrometers typically employ infrared technology to detect the thermal radiation emitted by an object, providing a non-contact method to gauge temperature. This feature is crucial in industrial settings, such as steel manufacturing or glass production, where traditional contact thermometers would be unsafe or insufficient due to the extreme heat.

In contrast, a thermometer primarily measures temperature through direct contact with a substance; it may not be suitable for all surface temperatures, particularly those that exceed its range or require quick measurements. A barometer is designed to measure atmospheric pressure, while a hydrometer measures the density or specific gravity of liquids, making each of them inappropriate for measuring surface temperature.