Definition:Local Gravitational Constant
Definition
The local gravitational constant is the value of the acceleration $g$ caused by the gravitational field given rise to by whatever body or bodies are in a position to exert that gravitational force.
In the everyday context, $g$ is the acceleration due to the gravitational field of Earth at whatever point on or near its surface the observer happens to be.
Thus in this context it is approximately equal to $9 \cdotp 8 \ \mathrm {m \, s^{-2} }$.
Symbol
- $g$
The force exerted on a body at (or near) the surface of the Earth under the influence of the gravitational field given rise to by the Earth.
Its $\LaTeX$ code is g .
Values
The local gravitational constant at the surface of Earth varies according to location, as can be seen from the following examples:
| \(\ds g\) | \(\approx\) | \(\ds 9 \cdotp 7801\) | $\mathrm {m \, s^{-2} }$ | \(\quad\) at the equator | ||||||||||
| \(\ds g\) | \(\approx\) | \(\ds 9 \cdotp 8321\) | $\mathrm {m \, s^{-2} }$ | \(\quad\) at the North Pole | ||||||||||
| \(\ds g\) | \(\approx\) | \(\ds 9 \cdotp 8119\) | $\mathrm {m \, s^{-2} }$ | \(\quad\) at London |
Standard Gravity
The standard gravity is a value of the local gravitational constant at the surface of Earth defined by international standard ISO/IEC 80000 as:
| \(\ds g_0\) | \(=\) | \(\ds 9 \cdotp 80665\) | $\mathrm {m \, s^{-2} }$ | \(\quad\) in SI units | ||||||||||
| \(\ds \) | \(\approx\) | \(\ds 32 \cdotp 17405\) | $\mathrm {ft \, s^{-2} }$ | \(\quad\) in FPS units. |
Also see
- Acceleration Due to Gravity
- Acceleration Due to Gravity at Earth's Surface
- Gravity at Earth's Surface
- Results about local gravitational constants can be found here.
Sources
- 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): local gravitational constant
- 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): acceleration of free fall (acceleration due to gravity)
- 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): acceleration of free fall (acceleration due to gravity)