Lab 4 projectile motion answers

Projectile motion is a part of our everyday experience. When you strike a baseball or softball, you are creating a projectile motion scenario. Similarly, you yourself are a projectile when you jump into a pool to cool off on a sweltering summer day. In this lab you will get some hands-on experience with projectile motion and apply the two-dimensional kinematic equations that we have developed. You will perform experiments and compare your results to theory.

This activity is based on Lab 7 of the eScience Lab kit. Although you should read all of the content in Lab 7, we will be performing a targeted subset of the eScience experiments.

Our lab consists of two main components. These components are described in detail in the eScience manual (pages 83-88). Here is a quick overview:

In the first part of the lab, you will launch a marble off of a table or other elevated surface and measuring the horizontal distance that the marble travels. From this distance, you will calculate the launch velocity of the marble. You'll then repeat the experiment using a different launch height and try to predict the new horizontal distance using the velocity that you derived from the first part of the experiment.
In the second part of the lab, you will launch small foam rockets. The first part of this experiment involves measuring the flight time of the rocket and deriving launch speed. In the second part of the experiment, you will explore the dependence of range on launch angle.
Note: In the rocket experiment, perform and document steps 1-7. Then launch your rocket at three angles: 30 degrees, 45 degrees, and 60 degrees. Record all of your data in the tables that are provided in this document. Don't use the tables in the eScience manual.

Take detailed notes as you perform the experiment and fill out the sections below. This document serves as your lab report. Please include detailed descriptions of your experimental methods and observations.

Experiment Tips:

Marble on a ramp

Although you are welcome to use the water and corn starch technique outlined in the eScience lab manual, I used a slightly less messy technique. Take a towel and fold it into several layers. Place the towel in the marble landing area and smooth the surface with your hand. When the marble hits the towel, its landing is deadened and you will see a slight impression of where it landed. Measure to this impression to determine the range of the marble.
Make sure that you place your marble at the same position on your ramp. This helps insure the repeatability of launch speed.