Projectile Motion

Formulas §

• We use A LOT of different formulas to calculate projectile motion.
• Formulas for linear motion.

Introduction §

• A projectile is any object which the only force is gravity.
• Projectiles travel with a parabolic trajectory due to the influence of gravity.
• There are no horizontal forces acting upon projectiles and thus no horizontal acceleration (assume negligible air resistance)
• The horizontal velocity of a projectile is constant.
• There is a vertical acceleration caused by gravity.
• The vertical velocity of a projectile changes by $9.8m{s}^{-1}$ each second.
• The horizontal motion of a projectile is independent of its vertical motion.

Projectiles launched horizontally §

• The projectile will be launched with an initial horizontal velocity at an elevated position.
• The path is a parabolic from this point to the ground.
• Predictable unknowns include the initial speed of the projectile, the initial height of the projectile, the time of flight, and the horizontal distance of the projectile.

Strategy for Solving Projectile Problems §

1. Carefully read the problems and list known and unknown information in terms of the symbols of the kinematic equations. For convenience sake, make a table with horizontal information on one side and vertical information on the other side.
2. Draw a diagram of the problem to help clarify what is going on in the question.
3. Identify the unknown quantity that the problem requests you to solve for.
4. Review the equations available and select the most adequate equation to use (or rearrange some equations)