## Horizontal Projectile Motion Math

### Create a Separate X and Y Givens List

Horizontal projectile motion math problems start with an object in the air beginning with only horizontal velocity. These problems often start with an object rolled off a table, being thrown horizontally, or dropped by a plane.

When we approach horizontal projectile motion problems separating the x and y components and work through problems keeping those givens separate.

When you see a problem with an object in the air traveling going forward but under the influence of gravity, create a separate X and Y givens list.

**Projectile Motion Equations**

Look at the equations used in projectile motion below. In the X axis you will only use our constant motion equation. Below you will see v_{x }which is just velocity in the x axis.

In the Y axis you will use our common acceleration equations. Below they are just specialized for something in the air. Our normal variable **a** (acceleration) is exchanged for **g** (acceleration due to gravity). **X** is exchanged for **Y **since the object will be moving in the Y axis. Also the **v _{i }**and

**v**are replaced with

_{f}**v**and

_{iy}**v**just representing that the velocities are only Y axis components.

_{fy }Horizontal projectile motion problems will have separate X and Y givens with only time being in both givens list. Projectile motion problems end when the object hits the ground. At that moment the projectile is done going forward and falling.

### Two ways to find time:

- If you have the Y displacement you can find time using Y axis givens. Don't forget that v
_{iy }= 0 m/s and g = 0 m/s^{2} - If you have horizontal velocity (v
_{x}) and X axis displacement (X), you can find time in this axis

**Example:**

**Joe throws a ball 9.4 m/s horizontally forward from the second floor 6 meters off the ground, how far downrange does it land?**

**Example:**

**A ball rolls off a table at 3.0 m/s and lands 2.5 meters away. How high was the table?**

### Horizontal Projectile Motion Math Quiz

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