# Force: Gravity

Model ElementForce_Gravity defines the acceleration due to gravity along the global X, Y, and Z directions.

## Format

<Force_Gravity

grav_x = "real"

grav_y = "real"

grav_z = "real" >
/>

## Attributes

grav_x
Defines the acceleration due to gravity in the global X direction. The default value is 0.0.
grav_y
Defines the acceleration due to gravity in the global Y direction. The default value is 0.0.
grav_z
Defines the acceleration due to gravity in the global X direction. The default value is 0.0.

## Example

The example below shows the gravity components in SI units.

<Force_Gravity
grav_x = "0."
grav_y = "0."
grav_z = "-9810."
/>

The following example shows gravity components modeled as a function of time.

<Force_Gravity
grav_x = "9810*STEP(TIME,0,0,2,1)"
grav_y = "0."
grav_z = "-9810*STEP(TIME,0,1,2,0)"
/>