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Remote Lab 8: Projectile motion Part (1): Objective: To show that the time of flight of a horizontal projectile is independent of its initial speed

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Remote Lab 8: Projectile motion 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/projectilemotion_en.html 2- Set the height at 15 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 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). 1 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). ……….…………………………………………………………………………………………………… ……….…………………………………………………………………………………………………… 8- What is the effect of air resistance on the range? ……….…………………………………………………………………………………………………… 2 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/projectilemotion_en.html 2- Set the height at zero level, H=0 m as shown: 3- Adjust the launcher at θ = 50o. 4- Set the initial velocity of the projectile vo at 21 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) 5.89 8.83 12.76 16.19 20.61 25.51 Time of flight (T) s Horizontal velocity of the projectile vx= X/T 7- Discuss your results in Table (2). ……….……………………………………………………………………………………………………… ……….……………………………………………………………………………………………………… 3 8- What are the velocity and the acceleration of the projectile at the highest point? ……….……………………………………………………………………………………………………… ……….……………………………………………………………………………………………………… 9- Calculate the velocity of the ball just before it hits the ground. ……….……………………………………………………………………………………………………… ……….……………………………………………………………………………………………………… 10- Study the effect of air resistance on the range and write down your conclusion. ……….……………………………………………………………………………………………………… ……….……………………………………………………………………………………………………… 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/projectilemotion_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 o 5- Adjust the launcher at 35 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 (35o, 45o, 55o, 65o, 75o, 85o) 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) o θ 35 45 55 65 75 85 vo= 15 m/s Sin (2θ) R (m) 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. 5 Questions: 1- Does a change in the angle of the projectile change the time of flight? If yes, explain how? ………….……………………………………………………………………………………………………… ………….……………………………………………………………………………………………………… 2- Refer to part (3), What angle produces the maximum range? Explain why. ………….……………………………………………………………………………………………………… 6