Units or magnitudes of Time
Time is a fundamental physical quantity that measures the duration of events. In physics, time is an important variable in many equations, such as the laws of mechanics and thermodynamics.
The unit of time in the International System of Units (SI) is the second (s). One second is the duration of 9,192,631,770 cycles of the radiation emitted by the cesium-133 atom.
Most popular units of time
- Minute (min): 60 seconds
- Time (h): 60 minutes
- Day (d): 24 hours
- Year (a): 365.2425 days
How to measure time
Time can be measured in various ways, using different instruments. The most common instruments to measure time are:
- Mechanical Watches: Mechanical watches use a gear mechanism to measure time.
- Quartz Watches: Quartz watches use a quartz crystal to generate an electrical signal that is used to measure time.
- Atomic Clocks: Atomic clocks use the properties of atoms to measure time with great precision.
Applications of time in physics
Time is a fundamental quantity in physics, and has applications in various fields of science. Some applications of time in physics are:
Mechanics: Time is an important variable in the laws of mechanics, such as the law of inertia or the law of the universal gravitational force.
Thermodynamics: Time is an important variable in the laws of thermodynamics, such as the law of conservation of energy or the law of the transformation of thermal energy into work.
Relativity: Special relativity and general relativity introduce new concepts about time, such as time dilation or time contraction.
Table of Time Units
| Unit | Abbreviation | Equivalence |
|---|---|---|
| Second | s | 1 second |
| Millisecond | ms | 1 second = 1000 milliseconds |
| Microsecond | Ξs | 1 second = 1,000,000 microseconds |
| Nanosecond | ns | 1 second = 1,000,000,000 nanoseconds | ms | 1 second = 1000 milliseconds |
| Microsecond | Ξs | 1 second = 1,000,000 microseconds |
| Nanosecond | ns | 1 second = 1,000,000,000 nanoseconds |
| Minute | min | 1 minute = 60 seconds |
| Hour | h | 1 hour = 60 minutes |
| Day | d | 1 day = 24 hours |
| Week | sem | 1 week = 7 days |
| Month (average) | month | 1 month â 30.44 days |
| Year (average) | year | 1 year â 365.25 days |