LABORATORY EXPERIMENTS IN PHYSICS
STUDENT LAB REPORT
Experiment
: Projectile Motion
Name
: ……………………..
Date : ………………
Part (1):
Objective: To show that the time of flight of a horizontal projectile is independent of its initial
speed.
Procedures:
1- Open the following link (from PHET Simulation):
https://phet.colorado.edu/sims/html/projectile-motion/latest/projectile-motion_en.html
2- Set the height at 12 m, or any value between (10 -15) m.
3- Adjust the angle of the launcher θ at zero degree.
4- Set the velocity of the launcher at 7 m/s and fire the ball then measure the timer of flight
(T) at the point where the ball hits the ground.
5- Repeat the previous step for four different values of velocity as shown in table 1 and
measure the corresponding time (T).
6- Report your data in Table (1).
1
Table (1)
V (m/s)
Time of flight
(T) s
7
11
13
19
24
Comment:
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7- Discuss the results in Table (1).
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8- What is the effect of air resistance on the range?
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Part (2):
Objective: To verify that the horizontal component of the velocity (vx) of the projectile is
constant during its motion.
Procedures:
1- Open the same link:
https://phet.colorado.edu/sims/html/projectile-motion/latest/projectile-motion_en.html
2- Set the height at zero level, H=0 m as shown:
3- Adjust the launcher at θ = 40o.
4- Set the initial velocity of the projectile vo at 19 m/s. (you are free to select the initial velocity)
5- Fix the height (H), initial velocity (vo) and the angle (θ) at the above values and don’t
change them during this part.
6- Measure the time of flight for different horizontal distances as shown in the Table 2.
Table (2)
Distance X
(m)
7.50
9.93
Time of
flight (T) s
Horizontal velocity of the
projectile vx= X/T
11.66
15.20
19.51
24.50
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7- Discuss your results in Table (2).
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8- What are the velocity and the acceleration of the projectile at the highest point?
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9- Calculate the velocity of the ball just before it hits the ground.
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10- Study the effect of air resistance on the range and write down your conclusion.
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Part (3):
Objective: i- To study the relationship between the angle of the projectile and its angle .
ii- To find the acceleration of gravity gexp
Procedures:
1- Open the same link:
https://phet.colorado.edu/sims/html/projectile-motion/latest/projectile-motion_en.html
2- Click on Lab
3- Leave the settings to the right of the screen as they are.
4- Set the initial speed at 20 m/s
5- Adjust the launcher at 30
o
4
6- Click on the red button below and release the projectile
7- Move the red circle horizontally toward the projectile target and measure the range R
8- Record the angle (θ) and the range (R) in table 3 in your lab report
9- Repeat steps 6-8 for the angles (34o, 43o, 52o, 60o, 71o, 86o)
10- Calculate sin (2θ) and record that in Table 3
11- Draw the range (R) versus the angle (θ) using Excel (Hint: this relation is not linear)
12- Draw the range (R) versus sin (2θ) using Excel, then find the slope of the line
Table (3)
θo
23
vo= 20 m/s
Sin (2θ)
R (m)
34
43
52
60
5
71
86
Slope= …………………………………………
13- From the slope of (R-sin2θ) graph, calculate the acceleration of gravity:
gexp= ……………………………………………
14- Calculate the percentage error in g:
g % 
………………………………………
15- Attach the graphs to your lab report
Questions:
1- Derive the following equation: t 
2y
g
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2- Does a change in the angle of the projectile change the time of flight? If yes, explain how?
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3- Refer to part (3), what angle produces the maximum range? Explain why.
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Conclusions:
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