Determining the Initial Velocity (Photogate Method)
angle = 0
I used the following method to calculate the initial velocity:
1
x f =x 0 +V x 0 t + a x t 2
2
V xo =
xf
t
The percent difference between the average velocity Range Method and average velocity

Determining the initial Velocity (Range method)
ANGLE = 0
Iusedthefollowingmethodtocalculatethetimeofflight:
1
y f = y 0 +V y 0 t + a y t 2
2
t=
y0
a y /2
I used the following method to calculate the initial velocity:
1
x f =x 0 +V x 0 t + a x t 2
2
V x

angle= 30
The percent difference between the predicted value of the range and the resulting average range
measured when shot at an angle:
predicted range = 1.15 m
% difference = 0.86%
Vertical Displacement = 0.255 m
Time of flight = 0.228 s
Equations used

SAMPLE CALCULATIONS
Range method:
Calculate the predicted value of the range:
Adjust the projectile launcher to an angle of 30. Record the new vertical displacement in Table 3. Using your
average overall initial velocity for the Range Method from Investig

The instantaneous velocity is equal with the average velocity when the speed is constant, which implies
acceleration = 0.
c.
Was your percent difference between these two quantities acceptable? Explain why or
why not.
The percentage was 0.98%, which is go

For angled launch position
6.
You predicted a range for your angled launch.
a.
How did your predicted range compare to the average range you found?
Both are greater that the range of the horizontal launch, and both are pretty close to eachother. (1.15m
an

Example for trial 1:
V x 0=
xf
0.234 m
=2.72 m/s
=> V x 0=
0.086 s
t
Overall velocity calculations:
Because the angle is 30 degrees, we can use the following equation: V 0 x =V 0 cos 30
Example trial 1:
2.72 m/ s=V 0 cos 30 => V 0=
2.72 m/s
=3.14 m/s
cos

Sample CALCULATIONS
Range method
Calculate the time:
1
y f = y 0 +V y 0 t + a y t 2 Here we can see that the only unknown is t. Substract t.
2
V y 0=0 m/ s
t=
a y =9.8 m/ s
2
y f =0 m
y0
0.242 m
=> t=
=> t=0.22 s
a y /2
4.9 m/s 2
Calculate the initial v