What is the SI unit of time?

The SI unit of time is the second. This is a fundamental unit in the International System of Units (SI), which is widely used in scientific measurements. The second is defined based on the vibrations of cesium atoms, providing a precise and consistent measure of time that can be universally applied in scientific contexts.

In contrast, hours, minutes, and days are all larger units of time that are derived from seconds. For example, one hour is equivalent to 3600 seconds, and one minute is equal to 60 seconds. While these units are commonly used in everyday life for convenience, they are not considered SI units. The second serves as the base unit for time, making it essential for scientific calculations, experiments, and technical applications where precision is critical.