PHY 101L Module Three Lab Report Projectile Motion

PHY 101L Module Three Lab Report Projectile Motion Name: Ashley Shaw Date: 01/27/24 Complete this lab report by replacing the bracketed text with the relevant information. Activity 1: Horizontal Projectile Motion Data Table Activity 1 Table 1 Tria l Spher e θ a = 0.71(9.8)sinθ 𝒗 𝒙 = √(2 𝒂𝒔 ) 𝑡 = √(2 ℎ / 𝒈 ) Calculated Distance 𝑥 = 𝒗 𝒙 𝑡 Actual Distance Percent Difference 1 Steel 10° 1.21m/s2 1.4m/s 0.17s 0.24m 0.39m 62.5% 2 Steel 15° 1.80m/s2 1.71 m/s 0.17s 0.29m 0.51m 75% 3 Steel 20° 2.38 m/s2 3.86 m/s 0.17s 0.66m 0.74m 12% 4 Acrylic 10° 1.21m/s2 1.4 m/s 0.17s 0.24m 0.32m 33.3% 5 Acrylic 15° 1.80m/s2 1.71 m/s 0.17s 0.29m 0.42m 44.8% 6 Acrylic 20° 2.38 m/s2 3.86 m/s 0.17s 0.66m 0.58m 12% Activity 1: Questions 1. Did the sphere in the experiment always land exactly where predicted? If not, why was there a difference between the distance calculated and the distance measured? The sphere only landed close to the calculated distance when the angle and acceleration increased in both of the 20° trials. With a percent difference of 12%. This was the closest the balls came to the predicted target. 2. Why is it important to use the grooved ruler to ensure that the sphere leaves the table in a horizontal direction? The ruler grooves ensure the ball travels in the same direction on the x-axis. 3. If the same experiment were performed on the moon, what would be different? Gravity is not the same on the moon therefore our calculations would be off from the start. The moons gravity is 1.625 m/s2, this would let the ball travel farther with a slower

acceleration and with added time. My calculations were for a 10° angle and my table eight of 0.81m. a=0.2 m/s2 t=1.0s 4. What is different about the vertical component of the sphere’s velocity and the horizontal component of the sphere’s velocity once the sphere leaves the table? The vertical component of the velocity remained constant at 9.8m/s (gravity) The horizontal was reduced as a result of the vertical component of gravity. 5. If the same experiment were repeated with the same angles, but from a taller table, how would the results change? The calculations that would change with a higher table would be the velocity and the time it takes. With a higher table the time would also increase, and the ball would gain in velocity. If my table were to increase .10m my new calculations would be: 𝒗 𝒙 = 2.2 m/s 𝑡 = 0.19s An increase happened in both, almost double the velocity and a slight increase in time. Activity 2: Exploring Projectile Motion with a Simulation In this activity, you will explore how altering the variables of the initial launch condition of a projectile affects the projectile’s trajectory. Adobe Flash is required for the PhET projectile motion simulator website. The simulation will allow you to change the following variables: Angle : This is the angle between the launch vector and the horizontal. Initial Speed: This is the speed of the projectile when it leaves the barrel of the cannon. Mass: This is the mass of the projectile. This is only a factor if air resistance is selected. Diameter : This is the diameter of the projectile. This is only a factor if air resistance is selected. Initial Position : You can control the initial position ( x and y ) by dragging the cannon with the mouse. You can measure the height by using the tape measure icon. Air Resistance : There is a check box for air resistance. For this activity, make sure the box is not checked. Air resistance will be ignored for this activity. Changing the initial conditions will affect the following variables, which are indicated in windows at the top of the simulation’s screen: Range : This is the horizontal distance measured from the launch position to where the projectile lands on the ground, or at the point where y = 0. The y coordinate for the projectile’s

4 4 7.3 0.25 20 0 Bowling Ball 18.06m -4m 0.9s 5 5 7.3 0.25 20 0 Bowling Ball 20.19m -5m 1.01s 5 6 7.3 0.25 20 0 Bowling Ball 22.12m -6m 1.11s 7 7 7.3 0.25 20 0 Bowling Ball 23..89m -7m 1.19s 8 8 7.3 0.25 20 0 Bowling Ball 25.54m -8m 1.28s 9 9 7.3 0.25 20 0 Bowling Ball 27.09m -9m 1.35s 10 10 7.3 0.25 20 0 Bowling Ball 28.56m -10m 1.43s Activity 2: PhET Simulation Data Table 3 Table 3 Variable: Launch Angle Trial Initial Height (m) Mass (kg) Diameter (m) Initial Speed (m/s) Angle (°) Projectile Range (m) Height (m) Time (s) 1 1 7.3 0.25 20 0 Bowling Ball 9.03m 1m 0.45s 2 1 7.3 0.25 20 10 Bowling Ball 18.27m 2m 0.93s 3 1 7.3 0.25 20 20 Bowling Ball 28.72m 3.5m 1.53s 4 1 7.3 0.25 20 30 Bowling Ball 36.97m 6.5m 2.13 5 1 7.3 0.25 20 45 Bowling Ball 41.47m 11.5m 2.95s 5 1 7.3 0.25 20 50 Bowling Ball 40.98m 13.25m 3.19s 7 1 7.3 0.25 20 60 Bowling Ball 35.88m 15m 3.59s 8 1 7.3 0.25 20 70 Bowling Ball 26.57m 19.45m 3.88s 9 1 7.3 0.25 20 80 Bowling Ball 14.12m 20.25m 4.07s 10 1 7.3 0.25 20 90 Bowling Ball 0m 21.36m 2.04s Activity 2: PhET Simulation Data Table 4

Table 4 Variable: Initial Speed Trial Initial Height (m) Mass (kg) Diameter (m) Initial Speed (m/s) Angle (°) Projectile Range (m) Height (m) Time (s) 1 1 7.3 0.25 5 0 Bowling Ball 2.26m 1m 0.45s 2 1 7.3 0.25 10 0 Bowling Ball 4.52m 1m 0.45s 3 1 7.3 0.25 15 0 Bowling Ball 6.77m 1m 0.45s 4 1 7.3 0.25 20 0 Bowling Ball 9.03m 1m 0.45s 5 1 7.3 0.25 25 0 Bowling Ball 11.29m 1m 0.45s 6 1 7.3 0.25 30 0 Bowling Ball 13.55m 1m 0.45s Activity 2: Questions 1. For Table 2, the initial speed and launch angle were kept constant, and the height was increased. Your data should show that the horizontal range of the projectile increased with each trial. If the initial speed and launch angle were constant, how did increasing the height change the horizontal range? Increasing the height increased the range of the projectile because it had farther to fall. If we were to graph it and the slope was over one down two then the higher on the y-axis the farther on the x-axis the slope would take us even if everything else stayed constant. 2. For Table 3, the height and initial speed were kept constant, and the angle was increased. How did the launch affect the range? How did the launch angle affect the time of flight? The ball travelled more vertically (y-axis) than horizontal (x-axis) therefore the range was shorter. The launch angle increasing also increased the time until it was at a 90° angle. 3. Examine the data in Table 3. You should see that several angles have the same or nearly the same horizontal range. What do you notice about these pairs of angles? What is different about the trajectories of the projectiles when fired from these angles? Angles that have close ranges like 45° and 50° are only a 5° difference. However, this is the turning point, somewhere between these two angles the switch is made from an increase in the horizontal direction to the vertical direction. Height is increased and range is lessened.