SI Units of Measurement
Base Units
| Physical Quantity | Unit of Measurement |
|---|---|
| Length | Metre |
| Mass | Kilogram |
| Time | Second |
| Electric Current | Ampere |
| Thermodynamic Temperature | Kelvin |
| Amount of Substance | Mole |
| Luminous Intensity | Candela |
Derived Units
| Physical Quantity | Unit of Measurement |
|---|---|
| Angle | Radian |
| Frequency | Hertz |
| Force | Newton |
| Weight | Newton |
| Pressure | Pascal |
| Energy | Joule |
| Work | Joule |
| Heat | Joule |
| Power | Watt |
| Electric Charge | Coulomb |
| Potential Difference | Volt |
| Electromotive Force | Volt |
| Electric Resistance | Ohm |
| Electric Capacitance | Farad |
| Electric Conductance | Siemens |
| Inductance | Henry |
| Magnetic Flux | Weber |
| Magnetic Flux Density | Tesla |
| Radioactivity | Becquerel |
Scientists and Units of Measurements
Definitions of Some Derived Units
Radian: One radian is the angle subtended at the centre of a circle by an arc that is equal in length to the radius. A semicircle consists of π radians and a circle consists of 2 π radians
Hertz: One hertz being the unit of frequency is one cycle per second.
Newton: One Newton is the force required to produce an acceleration of one metre per second when applied to a mass of one kilogram.
Pascal: One Pascal is equal to 1 Newton per square meter.
Joule: One Joule as the unit of energy or work is equal to the work done by a force of one newton when its point of application moves one metre in the direction of action of the force.
One Joule as the unit of heat energy is defined as the amount of energy required to raise the temperature of one gram of water by one degree Celsius.