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# Ballistic Flight Parabolic Equation

KurtHeckman.Ballistic Flight Parabolic Equation

The **Ballistic Flight Parabolic Equation** calculator computes the parabolic equation coefficients based on the launch angle above the horizon (**θ**) at an initial velocity (**V**) assuming a constant downward acceleration (**g**).

**INSTRUCTIONS**: Choose units and enter the following:

- (
**V**) This is the initial launch velocity. - (
**θ**) This is the launch angle above the horizon. - (
**g**) This is the acceleration due to gravity (default is 9.80665 m/s^{2})

**Parabolic Flight Equation**: The calculator returns the equation of the parabola to match the flight.

#### Ballistic Flight Equations and Calculators:

- Ballistic Maximum Altitude: This is the maximum altitude achieved in free ballistic flight.
- Ballistic Maximum Range: This is the maximum horizontal range.
- Velocity to achieve a Max Ballistic Height: This computes the initial velocity required to achieve the max height.
- Ballistic Flight Time: This is the time duration of free flight.
- Ballistic Vertical Velocity: This is the vertical velocity at a given time.
- Ballistic Horizontal Velocity: This is horizontal velocity or ground speed.
- Vertical Position in Ballistic Flight: This compute the vertical position (y) at a given time within ballistic flight.
- Horizontal Position in Ballistic Flight: This compute the horizontal position (x) at a given time within ballistic flight.

#### The Math / Science

The formula for the parabolic flight equation is:

y = a•x² + b•x + c

where:

- a = -4 • M / R²
- b = 4 • M / R
- c = h (initial height)
- M is the Ballistic Maximum Altitude without h
- R is the Ballistic Maximum Range without h

The addition of the initial height (h) to the Max Altitude and Range have the effect of shifting the parabola to the right, when all that is wanted is a shift up.

One of the most common representations of a parabola in nature is an object moving in the gravitational field of a massive body, such as the projectile motion of a body affected by the Earth's gravity. The figure shows the parabolic trajectory typifying a projectile that is affected solely by gravity, **g**.

# References

[Figure] Initial velocity of parabolic throwing

Source: Wikipedia / Fizped (modified to include motion equation)

URL: http://en.wikipedia.org/wiki/Projectile_motion#mediaviewer/File:Ferde_hajitas1.svg

**Ballistic Flight Parabolic Equation**, references 2 equations/constants.

**Equations and Constants **

**Ballistic Flight Parabolic Equation**, is used in 2 calculators.

**Calculators**