EXPERIMENT 12:

IDEA

CHAPTER 10: PROJECTILE AND SATELLITE MOTION (HORIZONTAL PROJECTILES)

PART 1

TITLE: TABLE TILT (SPHERE VELOCITY) VERSUS TIME OF FLIGHT OF A HORIZONTAL PROJECTILE

Purpose: To determine how the velocity of a spherical horizontal projectile (induced by changing the tilt of a table) affects the time the ball is in the air.

SEARCH

Background Information/Literature Review: Physics teachers often claim that a bullet fired horizontally from a gun and a bullet dropped from rest straight down from the same height will reach the ground at the same time. This investigation will attempt to prove/disprove this theory by graphing table tilt (which ultimately affects sphere velocity) against the time it takes from the ball to go from the table top to the ground. (Fill in the additional information from the textbook or online sources that applies to this investigation. Make sure to cite the sources.) For this experiment, the following concepts could be considered for inclusion: scalar, vector, resultant, projectile motion, components of a vector, etc.

Background Information / Literature Review / Pictures / Equations (continued):

Citations (including pictures):

GUIDE

Hypothesis: If the table tilt (velocity) of the sphere increases, then the time it takes for the ball to drop from the edge of the table to the ground will __________ (increase, decrease, or stay the same). (Fill in the appropriate hypothesis.)

Materials List: table top (or long board or other flat surface), books/bricks or other objects to put underneath the flat surface to change its angle, protractor, timing device, spherical object (i.e. marble, golf ball, tennis ball)

Procedure: But books, or other objects underneath the legs of one end of a table to create a tilt. Measure the angle of the surface with the horizontal with your protractor and record it on the data table. Start a ball from rest on the upper end of the table and allow it to roll off the lower end of the table onto the floor. Time how long it takes for the ball to drop from the lower edge of the table to the floor and record this value. Put more books underneath the legs of the table to again change the tilt. Theoretically, this also increases the velocity of the falling sphere once it reaches the end of the table. Record the amount of time it takes for the ball to drop from the lower edge of the table to the floor again. Repeat this procedure until you have taken time measurements from 10 different angles.

Picture/Labelled Diagram: Insert 1-3 pictures of yourself performing the experiment into this lab report for the instructor to ascertain how the investigation was conducted.

Photographs copyright of Stephanie A. Blake

Data Table: Table Title (Sphere Velocity) versus Time of Flight of a Horizontal ProjectileTable Tilt (Degrees) Horizontal Projectile Time of Flight (s)

Graph: Create a graph of Table Tilt (measured in degrees) versus Horizontal Projectile Time of Flight (measured in seconds). You may substitute a computer made graph using Microsoft Excel or some other software if you prefer.

Data Analysis: This section is also known as “Show Your Work”. Here is where you show how you performed the mathematics of your experiment. Be sure to include units in your measurements. This is also where you will find the slope of the line for the graph (in decimal form including units) as well as the equation of the line IF the relationship between the dots is in fact a line.

Conclusion: This is a series of several paragraphs written with correct grammar that answers the following questions in complete sentences. You must use formal academic language. (Do not use “I”, “me”, “we”, “our”, etcetera.)

What was the independent variable? What was the dependent variable? What were the controlled variables? Did you achieve your purpose? What was the relationship between variables? How accurate was your hypothesis?

Why was the hypothesis was correct/incorrect? What events in the experiment were expected? What events in the experiment were not expected? What human error occurred (i.e. measurement errors, significant digit errors, mathematics errors, etc)? What equipment error occurred (i.e. friction, air resistance, improper calibration, broken equipment, etc)? How could the lab be improved? How could this lab apply to physics in the real world?

What similar experiment could be done next to further study this phenomenon? What would be the independent, dependent and control variables? What would the purpose be? What is the hypothesis concerning the relationship between the dependent and independent variables in this experiment?

APPLY

Application – The Physics of Daily Life: Take a picture with a cell phone, draw a picture, or download a picture from the internet of this idea occurring in your world. Imbed it in this laboratory report. Explain in 50-100 words how the phenomenon in the picture applies to this concept. Be sure to use appropriate equations, units, vocabulary and concepts when possible to support your photograph.

INQUIRE

Your Turn – Inquiry Investigation: Use the final paragraph of your conclusion to develop and execute your own experiment. Be sure to consult “How to Write a Lab Report” on pages 12 and 13 of this manual for additional guidance.

TITLE: ________________________________________________________________

Purpose: _______________________________________________________________

Hypothesis: _____________________________________________________________

Background Information/Literature Review: Include any relevant information and equations from the textbook, online, or other references. This portion of the report should be 3-5 paragraphs long and illustrate a connection between the material in the book and daily life. Be sure to cite the sources, even if it is the textbook or Wikipedia.

Materials List: List all chemicals, equipment, and supplies you will need.

________________________________________________________________________

Procedure: These are the STEP-BY-STEP instructions for your inquiry lab investigation.

Picture/Labelled Diagram: Insert 1-3 pictures of yourself conducting the experiment into this lab report.

Data Table: Insert your data table here.

Graph: Make a graph of the information found in your data table. Make the graph in the space below or on Microsoft Excel, or some other software tool. Make a line or curve of best fit, do NOT connect the dots. Be sure to title the graph and the X and Y axes.

Data Analysis: Perform any necessary calculations here.

Conclusion: This is a series of several paragraphs written with correct grammar that answers the following questions:

What was the independent variable? What was the dependent variable? What were the controlled variables? Did you achieve your purpose? What was the relationship between variables? How accurate was your hypothesis?

Why was the hypothesis was correct/incorrect? What events in the experiment were expected? What events in the experiment were not expected? What human error occurred (i.e. measurement errors, significant digit errors, mathematics errors, etc)? What equipment error occurred (i.e. friction, air resistance, improper calibration, broken equipment, etc)? How could the lab be improved? How could this lab apply to physics in the real world?

What similar experiment could be done next to further study this phenomenon? What would be the independent, dependent and control variables? What would the purpose be? What is the hypothesis concerning the relationship between the dependent and independent variables in this experiment?