+ Marble Earth Lab #6 1/28/13

+ Marble Earth Lab #6 What you need: Lab report Pencil Your soda bottle marble

+ Marble Earth Lab #6 Procedures: Write down your question. Form a hypothesis (If…..Then… Statement) Test your hypothesis Put the marble in your soda bottle Screw the top back on your soda bottle Holding the top of the soda bottle: Marble at the bottom of the soda bottle Hold soda bottle at a 15° angle Swirl the marble in a clockwise direction until the marble creeps up the wall of the bottle

+ Marble Earth Lab #6 Procedures: Analyze your results What did your experiment show you The force that keeps Earth from flying into the Sun is the same force that keeps the marble on the sides of the soda bottle. That force is called: Centrifugal Force (force that acts outward on a body moving around a center). If not for this force, then the Earth would crash into the sun. The Marble stays in orbit because of the sides of the soda bottle. Similarly, the gravitational pull (the attraction that one object has for another object based on the invisible force of gravity) of the Sun keeps the Earth in place. The speed of the marble keeps it racing around the center of the bottle. Similarly, the speed of Earth’s orbit (average velocity of approximately 30,000 meters per second) keeps it from getting any closer to the sun. The effect of the sun’s gravitational pull on our planet is offset by centrifugal force generated during Earth’s orbit.

+ Marble Earth Lab #6 Draw Conclusion Agree or Disagree with your hypothesis Communicate Results Make sure to complete your experiment and lab report.

+ Review your Lab report Problem: Rewrite the problem statement as a question. Do not add anything to the question that is not in the problem statement; do not omit anything from the problem statement. Research / Background: Record information that you already know about this experiment and / or have looked up specifically for this experiment. Variables Constants: Variables that are not changed. There is usually more than one constant. Independent Variable: The one variable that you change. Also know as the manipulated variable. Dependent Variable: The one variable that changes because of what you did to the independent variable. Also known as the responding variable.

+ Review your Lab report Hypothesis : Written as an “If... then” statement. For example: If I do this to the independent variable, then I will observe this change to the dependent variable. Be specific about what you will do and what you expect to observe. Experiment Materials: Neatly list the items that will be used in the experiment and the quantity of each item. Procedure: List the steps taken to carry out the experiment. Number and write the steps in the order they were completed. Sketches are always good. Observations This is an opportunity to describe important aspects you encountered during the experiment and how you dealt with them. Report the data you collected from the experiment by using tables with appropriate labels and units. The table will show the data from multiple trails and their averages.

+ Review your Lab report Analysis Results Create an appropriate graph that clearly and accurately shows data from the experiment. Do not forget the title and to use labels and units. Provide a written summary that analyzes all of the data collected. Draw a Conclusion Restate your hypothesis word-for-word. Then, tell if it was correct or incorrect. If correct, give reasons why. If incorrect, tell why and what you would do differently next time. Use data from the experiment to back up your conclusion! Communicate your Results How will you tell others about your lab results from your experiment.