PASCO ME-6800 Projectile Launcher (Short Range) - Manual (Page 43)

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M o d e l N o . M E - 6 8 0 0 T e a c h e r ’ s G u i d e
0 1 2 - 0 5 0 4 3 G 39
Teacher’s Guide
Exp. 1: Projectile Motion
NOTE: For best results, make sure that the Launcher is securely clamped to a sturdy table. Any movement of the
Launcher will result in inconsistent data.
The muzzle speed of the Launcher tested was 6.5 m/s (on the long range setting).
To find the range at the chosen angle, it is necessary to solve the quadratic equation given in the Theory section.
The solution is:
Analysis
1. The difference depended on the angle at which the Launcher was fired. The table gives typical results: range
NOTE: The maximum angle is not 45° in this case. The range at 60° is not equal to the range at 30°. This is
because the initial height of the ball is not the same as the impact point. The maximum range for this setup
(with the Launcher 1.15 m above ground level) was calculated to be at 39°. This was verified experimentally.
2. Answers will vary depending on the method for estimating the precision. The primary source of error is ignor-
ing the effect of air resistance.
Exp. 2: Projectile Motion Using Photogates
Except for the method of determining initial speed, this experiment is identical to experiment 1.
Angle Predicted Range Actual Range Percent Error
30 5.22 5.19 0.57%
45 5.30 5.16 2.64%
60 4.35 4.23 2.87%
39 5.39 5.31 1.48%
t
v
0

v
0

sin
  2
2g y
0
y –
 
+ + sin
g
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