Projectile Motion
- The trajectory of an object undergoing projectile motion consists of a vertical component and a horizontal component
- These need to be evaluated separately
- Some key terms to know, and how to calculate them, are:
- Time of flight: how long the projectile is in the air
- Maximum height attained: the height at which the projectile is momentarily at rest
- Range: the horizontal distance travelled by the projectile
How to find the time of flight, maximum height and range
- Remember: the only force acting on the projectile, after it has been released, is gravity
- There are three possible scenarios for projectile motion:
- Vertical projection
- Horizontal projection
- Projection at an angle
- Let’s consider each in turn:
Worked Example 1
How to calculate vertical projection (free fall)
Worked Example 2
How to calculate horizontal projection
Worked Example 3
How to calculate projection at an angle
Exam Tip
Make sure you don’t make these common mistakes:
- Forgetting that deceleration is negative as the object rises
- Confusing the direction of sin θ and cos θ
- Not converting units (mm, cm, km etc.) to metres
