PHYS Exp 3 Projectile Motion V 2023

Projectile Motion – Online Version Purpose You will investigate the motion an object undergoing projectile motion. Background We have seen that objects in motion tend to obey a set of kinematic equations that we can use to describe the position, velocity, and acceleration of an object at any given time. In general practice, there are up to three dimensions, usually labeled x, y, and z. Each of these dimensions has its own set of kinematic equations tied to the velocity and acceleration in that direction. Usually, the equations are independent of one another and only have time as a common variable. Projectile motion is the special case where motion in the vertical direction is determined by free-fall, that is, motion with a constant acceleration of gravity downward, while in the horizontal direction, we assume that the acceleration is zero (neglecting air resistance). This means that the horizontal velocity is uniform. How far the object travels horizontally depends not only on the initial velocity, but also the amount of time the projectile is in the air. This time depends both on how far the projectile starts above the ground and whether or not there is any vertical component to the velocity initially from an angled launch. Procedure Part I: Angled Ball Launch, Symmetric 1. Open the Projectile Motion simulator by going to the following website: https://phet.colorado.edu/sims/html/projectile-motion/latest/projectile-motion_en.html , and click the far right option, Lab. 2. On the right side of the Lab simulator find the settings for the projectile. Verify that you will be shooting a Cannonball with the initial settings for Mass and Diameter. Use the standard 9.81 m/s 2 value for Gravity, and make sure Air Resistance is un-checked.

Figure 1 3. Use the slider at the lower left to set the initial speed of the projectile to 23 m/s. Only use 23 m/s to receive grade. 4. Click and drag the barrel of the cannon to change the angle to 25°. 5. Click the red button at the bottom of the screen to fire the cannon. Figure 2 6. Find the box of measurement tools near the top right of the screen. Select the blue tool by clicking and dragging it out of the box. Figure 3 7. Click and drag the measurement tool such that its cross-hairs are over the projectile’s point of impact. Record the Time and Range in Table 1. Before you continue the experiment, try to guess/predict at what angle you think the range will be highest (maximum range). You’ll later be asked to compare your prediction to the actual maximum angle of maximum range. Be honest! You’re not going to lose points for being wrong; remember, in science we learn by honestly comparing our predictions to the actual results of the experiment.

Data Table 1 Launch Angle Time of Flight (s) Range (m) 25° 1.98s 41.31m 30° 2.34s 46.7m 35° 2.69s 50.67m 40° 3s 52.86m 45° 3.3s 53.67m 50° 3.59s 53.11m 55° 3.84s 50.67 60° 4.06s 46.7m 65° 4.25s 41.31m Table 2 Launch Angle Time of Flight (s) Range (m) 0° 1.01s 23.22m 5° 1.23s 28.28m 10° 1.5s 33.88m 15° 1.78s 39.65m 20° 2.09s 45.2m 25° 2.41s 50.14m 30° 2.72s 54.17m 35° 3.03s 57.02m 40° 3.32s 58.51m 45° 3.6s 58.53m 50° 3.86s 57.01m 55° 4.09s 53.96m 60° 4.3s 49.43m 65° 4.48s 43.52m 70° 4.63s 36.4m 75° 4.74s 28.24m Analysis

1. Using the data from Table 1 and Excel to plot a graph of Range vs Angle for the symmetric case on Graph 1 below. Graph 1 2. Using the data from Table 2 and Excel to plot a graph of Range vs Angle for the non- symmetric case on Graph 2 below.