NAME: NAME: Date: TOE INVESTIGATION 3 POGIL

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1 NAME: NAME: Date: Goal for the Lesson: TOE INVESTIGATION 3 POGIL Use the concept of energy transformation to describe how the energy of a pendulum changes during each swing. Use your knowledge of kinetic and potential energy to identify the different forms of energy of a pendulum and how each form changes in size during the swing of the pendulum Use the Particle Model and the concept of energy transfer to explain where the energy of the swinging pendulum eventually goes. Pd: Lesson Essential Question: INVESTIGATION OVERVIEW: This demonstration will allow us to discuss the kinetic energy, the gravitational potential energy, and the heat energy associated with the swinging pendulum. We should be able to draw upon the discoveries from the previous investigations to describe the energy transfers and transformations during this pendulum swing. During the second part of the demonstration, the water is emptied from the bottle and the investigation is repeated. The outcome is drastically different, and you will be asked to apply what they have learned about the effect of mass on the kinetic and potential energies of an object to explain. Making Sense of Energy: What is energy? A REVIEW OF THE PARTICLE MODEL A Model to understand the structure of matter You may build model cars or know someone who does build them. Is the model exactly like the real car? In what ways is it different? You may have answered that the model car is smaller or that its engine can not work. Although there are some differences between the model car and the actual car, we can get a good idea of what the real car will look like and how it will behave by investigating the model. In science, we also use models to represent things that are difficult to see or understand. You may have discussed a model of the solar system because the actual solar system just wouldn t fit in a classroom. An important goal of this unit is to establish that when objects slide, bounce, or roll to rest, that their kinetic energy does not just disappear. This energy is transferred to the tiny particles that make up the objects involved. We will be talking about the extremely tiny particles that make up all matter. The model that best describes the behavior of these particles at this grade level is called the Particle Model. In later grades, this Particle Model will be improved upon to create a much more detailed model for understanding many concepts in chemistry and TOE POGIL

2 physics. Key Ideas about the particle model: Matter is composed of tiny particles. The particles of a single substance are the same, whether the substance is a solid, liquid or gas. Only the nature of the connections between particles changes when the phase of the substance changes. Particles are always moving (even in solids). Particles in solids vibrate around a fixed position. The extent of their motion is severely limited because of the connections that bind the particles of a solid together. These connections keep the particles closely packed together. Particles in liquids move more freely than do solids. The connections between particles in a liquid are weaker than in a solid, but strong enough to keep the particles close together. Particles in gases are moving freely and move as far apart from each other as their container allows. Adding energy, like heat, causes the particles to move more quickly and further apart. Adding energy will not change the size of the particles, but the total volume will tend to increase as the particles move away from one another as they vibrate more and more. Figure 1: The picture above is an analogy to the way solids, liquids, and gasses arrange themselves. The passengers on the bus are like particles in solids; they can move around a little, but are confined by the seats and others around them. The incoming passengers are like liquids; they have more freedom to move, but are bound by the door opening and aisle. The exiting passenger is like a gas; he is free to move around in many directions and has few restrictions on his movement. Figure 2: The picture above show the vibrations of the particles in a solid, liquid, and gas. The solid particles can not vibrate much without touching one another, but the gas particles have much more room to vibrate before touching one another. TOE POGIL

3 (Material Adapted from ON THE BALL, Particle Models for Key Stage 3 Science, Royal Society of Chemistry, University of Southhampton, 2001) REVIEW OF THE PARTICLE MODEL STATE OF MATTER HAS MAS S TAK ES UP SPA CE DEFI NITE SHAP E TAKES THE SHAPE OF THE CONTAINER SMALL AMOUNTS FILL A LARGE CONTAINER CAN BE INVISIB LE HOW DO THE PARTICLES MOVE ENERGY TRANSFERS BY WHAT TYPE OF HEAT TRANSFER KINETI C ENERGY CONNECTI PAR SOLID LIQUID GAS TOE POGIL

4 LET S INVESTIGATE Problem: How does mass of an object affect the amount of energy produced? Variables: Manipulated Variable: Responding Variable: Constants: Hypothesis: Lab Illustration: Materials: Procedure: TOE POGIL

5 Data: Trial #1 Trial #2 Trial #3 Trial #4 Trial #5 Filled Water Bottle Empty Water Bottle Question #1: Does the bottle and water have any energy? How do you know? Question #2: What is happening to the energy of the bottle of water? Question #3: Describe what forms of energy the pendulum has while it swings back and forth. Question #4: Describe the energy transformations that take place in each cycle of the motion. Question #5: Is there any evidence that energy is leaving the pendulum? What is the evidence? Question #6: Is the motion of the pendulum the same for each cycle? If it is, can you describe how the motion changes? Question #7: What variables are different in this part of experiment and what variables remain the same. TOE POGIL

6 Question #8: Of the variable(s) that have been changed how will they/it affect the energy of the pendulum? Question #9: Predict how the motion of the empty bottle will be different from the bottle filled with water. Question #10: Does the empty bottle slow down faster because it feels more resistance or because it has less energy to begin with? Application: A wrecking ball is used to knock down old buildings to make room for new construction. The wrecking ball is a very heavy solid steel ball, roughly the size of a garbage can. The wrecking ball is like a pendulum. It swings back and forth, hung by a strong cable from the top end of a tall crane. The crane swings the wrecking ball back and forth and into the walls of the old buildings. Describe what happens to the energy of the wrecking ball. Where does the energy of the ball come from and where does it go? TOE POGIL