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 15 m, or any value between (10 -15) m.

3- Adjust the angle of the launcher at zero degree.

4- Set the velocity of the launcher at 10 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).

Table (1)

V (m/s)	Time of flight (T) s
10
20
30
40
50

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 (v_x) 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 = 50^o.

4- Set the initial velocity of the projectile v_o at 21 m/s.(you are free to select the initial velocity)

5- Fix the height (H), initial velocity (v_o) and the angle () 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)	Time of flight (T) s	Horizontal velocity of the projectile vx= X/T
5.89
8.83
12.76
16.19
20.61
25.51

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 g_exp

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 25 m/s

5- Adjust the launcher at 35^o

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 () and the range (R) in table 3 in your lab report

9- Repeat steps 6-8 for the angles (35^o, 45^o, 55^o, 65^o, 75^o, 85^o)

10- Calculate sin (2) and record that in Table 3

11-Draw the range (R) versus the angle () using Excel (Hint: this relation is not linear)

12- Draw the range (R) versus sin (2) using Excel, then find the slope of the line

Table (3)

vo= 15 m/s
o	Sin (2)	R (m)
35
45
55
65
75
85

Slope= ................................................

13- From the slope of (R-sin2) graph, calculate the acceleration of gravity:

g_exp= ...................................................

14-Calculate the percentage error in g:

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15- Attach the graphs to your lab report.

Questions:

1- Does a change in the angle of the projectile change the time of flight? If yes, explain how?

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2- Refer to part (3),What angle produces the maximum range? Explain why.

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