Article on Solar Storms 3/10/11/solar- storms_n_ html
Notes: Energy
New Unit: Energy 13a - explain that energy is conserved according to the law of conservation of energy as energy is transformed from one form to another 13b - explain the relationship between potential and kinetic energy 13c- compare and contrast the different forms of energy (heat, chemical, nuclear, light, electrical, mechanical, and sound) and their characteristics 13d - explain how heat is transferred through matter by conduction, convection and radiation
Energy: The ability to do work
Work: occurs when a force causes an object to move in the direction of the force
Kinetic Energy: energy of motion
Potential Energy: energy an object has because of its position or shape
The law of conservation of energy: energy can neither be created or destroyed
1. Give an example of something that has potential energy. 2. Can something have potential energy AND kinetic energy at the same time?
Target Today We don’t have time for a target today. Please do the following: 1. Have your “Matter Children’s Story” out and ready to turn in when I ask for it. 2. Clear your table except for your notebook and be prepared for class. 3. Be on task, we need to move quickly and stick to schedule today!!
Mechanical Energy: Potential energy + Kinetic energy
Thermal Energy: energy of the particles that make up an object
Chemical Energy: potential energy of a compound
Electrical Energy: the energy of moving electrons
Electricity Video AFW4zdXpbY
Sound Energy: an object’s vibrations send waves through the air
Sound Energy Link
Nuclear Energy: energy released by the joining or splitting of atoms
Nuclear Energy Link
Energy Conversion: a change from one form of energy to another
Machines convert energy from one form to another
Whenever energy is converted to a different form, some is converted to thermal energy
Practice For each of the following examples, tell what type of energy you start with and what type/types of energy you finish with: 1. Hair Dryer6. Television 2. Alarm Clock7. Car stereo 3. Battery8. Lawn Mower 4. Light Bulb9. Your body 5. Blender10. Automobile
Warm-Up: 1. What type of energy does a gallon of gasoline have? 2. What type of energy does a bird in flight have? 3. A battery starts with ________and converts it to ____________.
Throughout your day, you come into contact with many different forms of energy. In one paragraph, describe your daily routine and tell about the different forms of energy you encounter throughout the day. Be sure to include at least 5 times you encounter energy.
Kinetic energy depends on speed and mass kinetic energy = 1 x mv 2 2 kinetic energy is measured in joules (J)
Warm-Up: Calculate the kinetic energy 1. A bird with a mass of 1 kg and a velocity of 10 m/s. 2. A tennis ball with a mass of.05 kg and a velocity of 9 m/s. 3. A baseball with a mass of.200 kg and a velocity of 40 m/s. 4. A school bus with a mass of 8000 kg and a velocity of 30 m/s. 5. A sprinter with a mass of 8000 g and a velocity of 7 m/s.
Give two examples of each kind of energy: 1. Kinetic 2. Potential 3. Chemical 4. Electrical 5. Thermal 6. Nuclear 7. Sound 8. Light
kinetic energy = ½ x mv 2 1. A sprinter with a mass of 100 kg and a velocity of 10 m/s. 2. An arrow with a mass of.02 kg and a velocity of 100 m/s. 3. A car with a mass of 1000 kg and a velocity of 20 m/s. 4. A train with a mass of 1,000,000 kg and a velocity of 30 m/s. 5. A 500 gram ball traveling at 10 m/s.
Warm Up: For each thing below, tell what kind of energy it starts with and what kind of energy it ends with: 1. Toaster 2. Car 3. Tree 4. CD player/stereo
Read about perpetual motion on pg Your friend tells you they invented a perpetual motion machine. What do you tell them in response? Support your answer.
Complete these practice problems: 1. What is the gravitational potential energy of a 100 N rock sitting on top of a 100 M hill? 2. What is the gravitational potential energy of a 10 N book on a shelf 2 M from the ground? 3. What is the kinetic energy of a 1 kg bird traveling at a speed of 15 m/s? 4. What is the kinetic energy of a bus with a mass of 10,000 kg bus traveling at 10 m/s? 5. What is the kinetic energy of a baseball with a mass of.2 kg thrown at 20 m/s? Short Answer: In about ½ page, explain what friction is, give at least 3 examples of it from your life, and explain why it is necessary for humans to function.
Target: (#13) Look at pg What are the three different temperature scales? 2. At what temperature does water boil and freeze in degrees Fahrenheit? 3. At what temperature does water boil and freeze in degrees Celsius?
Temperature: A measure of the average kinetic energy of the particles in an object.
Thermal Expansion: materials expand as their temperature increases
Heat is the transfer of thermal energy between two objects
Energy is always transferred from the higher temperature object to the lower temperature object to reach equilibrium
Conduction: transfer of thermal energy from one object to another through direct contact
Conductor: transfers energy well Insulator: does not transfer energy well
Radiation: transfer of energy through air or space as electromagnetic waves
Dark colors absorb more heat than light colors
Convection: transfer of thermal energy by the movement of a liquid or gas
Practice (list two examples each): 1. Example of conduction 2. Example of radiation 3. Example of convection
Target: (#11) 1. Which has more thermal energy: a cup of hot chocolate or the Pacific Ocean? 2. What is mechanical energy?
Target: (#11) 1. What are the three ways thermal energy can transfer? 2. List three types of energy other than thermal.
Target: (#12) 1. A gasoline powered lawn mower converts ______________ energy to ______________. 2. A nuclear power plant converts nuclear energy to _________________.
Warm-Up: 1. Which has more thermal energy: A cup of hot water at 60⁰ C or the Atlantic ocean with an average temperature of 30 ⁰ C? 2. For condensation to occur, thermal energy must be: A. addedB. removedC. kept the same