Year 12 Mechanics Projectile Motion Experiment 2:

**Projectile motion exp 1**
**Projectile motion exp 2**
**Projectile motion exp 3**
Find muzzle velocity by firing vertically
Find the muzzle velocity by shooting horizontally
- determine time of flight
- determine muzzle velocity
Find the position the projectile will land, by firing at an angle to the horizontal
- resolve x and y components of velocity
- determine time of flight
- determine horizontal distance.

Purpose:

  • The purpose of this experiment is to calculate the initial velocity (muzzle velocity) of the ball by firing the cannon horizontally.

NOTE: it is recommended that you do experiment 1 first (as their are less calculations)

Equipment:


  • Projectile launcher (ME-6801)
  • Stopwatch
  • 1m rulers
  • Bench
  • clamp (can be useful)
  • photo gates (use only for verification as they take a lot of the learning away)

Method:

projectile_launcher21.jpg
In this case, shooting the ball horizontally is the same as dropping the ball, in terms of the time to hit the ground (see Simultaneous fall demo), so vy =0ms^-1

projectile_launcher22.jpg

projectile_launcher23.jpg



Pitfalls / causes of error

  • The cannon MUST be perfectly horizontal (use plumb bob to check)
  • Generally very accurate (This can also be verified using photo gates)

Resources


Model data:

  • For one click using the above projectile launcher gave muzzle velocity of 4.21 ms-1.
  • 2 clicks gave a muzzle velocity (plastic balls) of 7.31 ms-1
projectile_launcher24.jpg

References / other comments: