Energy Basics First Law of Thermodynamics and Energy Transformations Integrated Science 4 Honors Name: Per:

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1 Energy Basics First Law of Thermodynamics and Energy Transformations Integrated Science 4 Honors Name: Per: To understand how natural and human-built systems work, we must clearly define what matter and energy are. Matter has energy. Matter stores energy and energy can be released from matter. There are many forms of energy. They all have different capabilities of doing work, which means they can exert a force on an object causing the object to move some distance. Energy comes from different sources and the sources of energy are all matter. Ø Part 1: The Relationship Between Matter and Energy Directions: Read pages 78 and in Global Science (Christensen, 2000) and answer the questions below. 1. Define matter and energy. 2. How are energy and matter related? 3. Restate the Law of Conservation of Matter. 4. Restate the First Law of Thermodynamics (Law of Conservation of Energy). Ø Part 2: The Various Forms of Energy Directions: Read the definitions below and then complete the flow chart to categorize various forms of energy. Refer to pages in Global Science (Christensen, 2000) for supplemental information. Please note that this is not the only manner in which to classify forms of energy. We will explore some other schemes in class. Various Forms of Energy Definitions 1. Mechanical Energy: The total energy an object has due to its position or movement. Either potential energy, kinetic energy, or both. For example, the potential energy in a bow when it is stretched back combined with the movement of the bow once it is released. 2. Potential Energy: Stored energy that is ready to be used due to an objects position or condition. For example, the energy stored in a spring, the stored energy of a rock on a ledge, the energy stored in the chemical bonds of two particles, the energy stored in the nucleus of an atom, and energy stored in a conductor of electricity. 3. Kinetic Energy: The energy of motion. The pattern of movement can be classified as random, wave, linear or rotational. For example, the energy of a thrown baseball, the energy carried by vibrating particles like sound. 4. Heat/Thermal Energy: The energy of moving particles that can change the temperature of something. For example, the heat you feel when you rub your hands together. 5. Light/Radiant Energy: The energy from electromagnetic waves. For example, light waves, solar radiation, radio waves, infrared radiation (lasers), microwaves, and x-rays. 6. Electrical Energy: This is the energy of electrons stored in or flowing through a conductor in a controlled motion. The flow of electrons is conducted through wires made of materials whose properties make this type of motion possible. For example, the energy transferred through electrical wires made of copper. 7. Chemical Energy: The energy stored in molecular bonds. This is the energy found trapped between the atoms that make up a given molecule. For example, photosynthesis - where the radiant energy from the sun is used to combine water (H 2 O) and carbon dioxide (CO 2 ) into glucose sugar (C 6 H 12 O 6 ) - most of the energy used is trapped within the bonds of the newly formed glucose. 8. Nuclear Energy: The energy stored in the nuclei of atoms. The energy can be released by: 1) radioactive decay: the spontaneous decay of large nuclei to smaller ones, which releases energy in the process; 2) fission: the purposeful breaking down of nuclei into smaller ones; 3) fusion: the process of small nuclei fusing together to make bigger ones.

2 Various Forms of Energy Flow Chart The total energy an object has due to is position, movement or both Energy that is stored and ready to be used, due to an object s position or condition. Energy that is released, due to an object s movement or motion. Examples: Examples: Ø Part 3: Energy Transformations- Qualitative Analysis 1. According to the First Law of Thermodynamics, energy cannot be created or destroyed, but can be converted, or transformed from one form into another. Energy transformations occur when we use energy. Consider the devices below. For each device, list the initial form of energy in the device and the converted form of energy. Device Initial Form of Energy Converted Form of Energy 2. Using your thinking from above, look at the devices pictured in Diagram 2. In each of the empty boxes below, write the number of the device (from Diagram 2.) that could convert energy from the form listed on the left side to the form named at the top. Refer to the light bulb example that has been done for you. Place only one number in a box and no number is used more than once.

3 Diagram 1. Energy Transformation Chart A.

4 Example: A. light bulb Diagram 2. Devices and Processes

5 Ø Part 3: Energy Transformations- Quantitative Analysis 1. In the Global Science textbook, review p. 95 (Section 3.9) and p (Appendix 5 and 6). Use the quantitative energy conversions provided to complete Activity 3.8 (p ). Everyone should complete questions If you sit on the right side of the room, by the windows, you should do the odd questions from If you sit on the left side of the room, away from the windows, you should do the even questions from For each problem, show your work. You must include the units with each step. Indicate your final answer, including the units, with a box. Pay attention to the number of decimal places you use in your final answer.