Projectile Motion will appear below in a Java enabled browser.

This Applet has several complementary applications. First, it compares several different algorithms using simple projectile motion to determine pros and cons of each. Second, it displays the trajectory of a projectile with or without air resistance and wind velocity. Finally, it allows application of the knowledge of basic kinematics laws, or just plain luck, in a simple, but fun, game.

**To use:**

To go into a detailed introduction and explanation of all of the features of this applet would require a huge page. Here, I will introduce the beginning user to the basics. For a more in-depth explanation of the applications and theory of the applet, click on the respective links below.

The **Fire** button "fires" a projectile out
of a cannon.

**Vo**, the initial velocity, can be varied, which
determines the velocity with which the projectile leaves the cannon.

**Theta**, the
initial angle, can be varied, which determines the angle at which the projectile
leaves the cannon.

The effects of resistance can be modeled by clicking the **Resistance** check box.
Notice that the path of the projectile is no longer parabolic.

Several physical properties of the projectile can be viewed by selecting a graph from the graph choice box, currently listed as "Energy." The available graphs are:

**Energy**: A graph that plots the Kinetic Energy (KE)
as a function of the Potential Energy (PE).

**X and Vx**: A graph that plots the x position and
velocity as a function of time.

**Y and Vy:** A graph that plots the y position and
velocity as a function of time.

**Error**: A graph that plots the algorithmic error as a
function of time, or inherently, the number of steps.

To change the view of the calculations from the Animation
to the individual data points, select "**Table**" from the view
choice bar, currently "**Animation**." You can compare two
different algorithms by selecting one at the top of the screen. The
available algorithms are **Euler**, **RK2**, and **RK4**. You
also have the choice of "Ideal," which is not a true algorithm, but
rather a kinematic calculation of the ideal position of the projectile at each
given point. Note that for all reasonable purposes, **RK4**
will work superbly.

Finally, for the fun-spirited, select **Play Game** and right click on the screen to select
a level of difficulty. The object
of the game is to hit the red target (without hitting the building full of
innocent civilians).

Those were the basics...

For a more in-depth explanation and an error analysis of the different algorithms:

For a description of the applications of this applet for the education of projectile motion:

For a brief description of the possibilities of the game:**
**

For Java programmers interested in the program, Borland JBuilder 3.0 created the following documentation, which is a detailed analysis of all of the classes and methods in this project.

Finally, as much as I would like to claim that all of the
work is a product of my own creativity and ingenuity, it is not. Click on
the following link to view the **references**