# Gravitational Acceleration

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Gravitational acceleration, abbreviated as g, also known as acceleration of gravity or acceleration due to gravity, is the force on an object caused only by gravity.

On Earth, the gravitational acceleration is a constant:

g = 9.80665 meters/ second2 (metric)

g = 32.1740 feet/ second2 (english)

For other bodies, the acceleration due to gravity, can be calculated below.

Gravitational Acceleration formula

$$\large{ g = \frac{G \; m}{r^2} }$$

$$\large{ g = \frac{ v^2 }{ h_m \; Fr^2 } }$$

$$\large{ g = \frac {PE} {m \; h} }$$

$$\large{ g = \frac{ p_b \;-\; p_t }{ \rho \; h } }$$     (fluid pressure)

$$\large{ g = \frac{ v^2 }{ 2 \; \left( NPSH \;-\; \frac{ p }{ \gamma } \;+\; \frac{ p_s }{ \gamma } \right) } }$$     (pump net positive suction head and cavitation)

Where:

$$\large{ g }$$ = gravitational acceleration

$$\large{ \rho }$$   (Greek symbol rho) = density

$$\large{ v }$$ = flow velocity

$$\large{ Fr }$$ = Froude number

$$\large{ h }$$ = height of depth of the liquid column

$$\large{ m }$$ = mass

$$\large{ h_m }$$ = mean depth

$$\large{ NPSH }$$ = net positive suction head

$$\large{ m }$$ = planet mass

$$\large{ PE }$$ = potential energy

$$\large{ p }$$ = pressure

$$\large{ p_b }$$ = pressure at bottom of column

$$\large{ p_t }$$ = pressure at top of column

$$\large{ r }$$ = radius from the planet center

$$\large{ \gamma }$$  (Greek symbol gamma) = specific weight

$$\large{ G }$$ = universal gravitational constant

$$\large{ p_s }$$ = vapor pressure

$$\large{ v }$$ = velocity