The provided reference lists only seven fundamental physical quantities, not fifteen. However, we can discuss those seven and then look at common derived physical quantities to approach the number fifteen. The seven fundamental quantities and their SI units are:
Fundamental Physical Quantities
Here are the seven base physical quantities:
| Physical Quantity | SI Unit | Symbol |
|---|---|---|
| Length | meter | m |
| Mass | kilogram | kg |
| Time | second | s |
| Temperature | Kelvin | K |
| Electric Current | ampere | A |
| Light Intensity | candela | cd |
| Amount of Substance | mole | mol |
Derived Physical Quantities
While the reference only gives the seven base units, there are many derived units we can consider. These are formed by combining base units:
Here are some common derived physical quantities, taking into account the need to get to 15:
- Area: Measured in square meters (m²). It is derived from multiplying length by length.
- Volume: Measured in cubic meters (m³). It’s a measure of three-dimensional space derived by multiplying length by length by length.
- Speed: Measured in meters per second (m/s). Derived from length divided by time.
- Acceleration: Measured in meters per second squared (m/s²). Derived by the change in speed per unit of time.
- Force: Measured in Newtons (N). Derived as mass times acceleration (kg*m/s²).
- Energy: Measured in Joules (J). Can be defined by Force times distance (N*m).
- Power: Measured in Watts (W). Joules per second, measuring rate of energy use (J/s).
- Pressure: Measured in Pascals (Pa). Force per unit area (N/m²).
- Density: Measured in kilograms per cubic meter (kg/m³). Mass per unit volume.
- Electric Charge: Measured in Coulombs (C).
- Voltage: Measured in Volts (V).
- Electric Resistance: Measured in Ohms (Ω).
- Frequency: Measured in Hertz (Hz). This is reciprocal of time (1/s).
- Momentum: Measured in kg m/s. This is mass times velocity
- Angular Velocity: Measured in radians per second (rad/s)
These are just some of the many physical quantities, and this list gets us to 15. Other possibilities include magnetic fields, electric capacitance, and so on, but the listed examples offer a good mix of quantities from various branches of physics.
