Slide1: Energy and Work Amusement Park Style
Objectives: Objectives Define work done by a force in a mechanical system Explain the relationship between work done, force applied and distance moved Identify effects of work done Solve work problems, given force and distance Explain how efficiency relates to input work and output work
Slide3: Energy and Work Types of Energy Forms of Energy Law of Conservation of Energy Amusement Park Physics and Activities Work Renewable and Nonrenewable Sources
Slide4: Renewable and Nonrenewable Sources Renewable Nonrenewable Main Menu
Slide5: Types of Energy Kinetic Energy Potential Energy Main Menu
Slide6: Forms of Energy Radiant Electrical Chemical Thermal Nuclear Magnetic Sound Mechanical Main Menu
Slide7: Radiant Energy Forms of Energy Radiant energy is also called electromagnetic energy. All life on earth is dependent on radiant energy from the sun. Examples of radiant energy include radio waves (AM, FM, TV), microwaves, X-rays, and plant growth. Active solar energy uses photovoltaic panels and light to turn radiant energy into chemical energy.
Slide8: Chemical Energy Chemical energy is the energy stored in the bonds of atoms and molecules. This a form of potential energy until the bonds are broken. Products that contain chemical energy include: TNT, baking soda, and a match. Biomass, petroleum, natural gas, propane and coal are examples of stored chemical energy. Forms of Energy
Slide9: Electrical Energy Electrical energy is the movement of elections. Lightning and static electricity are examples of electrical energy that occur naturally. Science hasn't found a way to use natural forms of electrical energy, like lightning. Instead, we use different energy sources to create electrical energy by using generators and turbines. Forms of Energy
Slide10: Nuclear Energy Nuclear energy is the energy stored in the nucleus of an atom. Nuclear energy is unusual in that it can give off energy in the form of light or heat, but it is the change in the atom's makeup that produces the energy. Submarines, power plants, and smoke detectors all use nuclear energy. Nuclear power plants use uranium, a radioactive element, to create electricity. Forms of Energy
Slide11: Thermal Energy Thermal energy is the internal energy in substances-the vibration and movement of atoms and molecules within substance. Thermal energy is created in the movement of atoms. Boiling water, burning wood, and rubbing your hands together really fast are all examples of heat energy. Geothermal and passive solar are sources of heat energy, but biomass (a type of chemical energy) can be burned to produce heat energy. Forms of Energy
Slide12: Sound Energy Sound energy is the movement molecules in the air that produces vibrations. Alarms, music, speech, ultrasound medical equipment all use sound energy. VCR tapes change sound energy into electrical energy. The electrical energy records the sound using magnetic tape. Speakers read the magnetic tape and change it back into sound. Forms of Energy
Slide13: Mechanical Energy Mechanical energy is the movement of machine parts. Mechanical energy is also the total amount of kinetic and potential energy in a system. Wind-up toys, grandfather clocks, and pogo sticks are examples of mechanical energy. Wind power uses mechanical energy to help create electricity. Potential energy + Kinetic energy = Mechanical energy Next
Slide14: Mechanical Energy Potential energy + Kinetic energy = Mechanical energy Forms of Energy Example of energy changes in a swing or pendulum.
Slide15: Magnetic Energy Magnetic energy is the attraction of objects made of iron. Medical equipment, compass, refrigerator magnets are all examples of magnetic energy. Any type of energy source that uses a generator in the process to make electricity uses magnetic energy. Forms of Energy
Slide16: Kinetic Energy Kinetic energy exists whenever an object which has mass is in motion with some velocity. Everything you see moving about has kinetic energy. The kinetic energy of an object in this case is given by the relation: KE = (1/2)mv 2 m=mass of the object V=velocity of the object The greater the mass or velocity of a moving object, the more kinetic energy it has. Kinetic Energy Lab Next
Slide17: Kinetic Energy The greater the mass or velocity of a moving object, the more kinetic energy it has. Kinetic Energy Lab Types of Energy
Slide18: Potential Energy Potential energy exists whenever an object which has mass has a position within a force field. The most everyday example of this is the position of objects in the earth's gravitational field. The potential energy of an object in this case is given by the relation: PE = mgh PE = Energy (in Joules) m = mass (in kilograms) g = gravitational acceleration of the earth (9.8 m/sec2) h = height above earth's surface (in meters) Potential Energy Lab Types of Energy
Slide19: Law of Conservation of Energy Law of Conservation of Energy- Energy can neither be created nor destroyed. Energy is always changing from one kind to another. The total energy of an object never changes. Potential energy + Kinetic energy = Total energy and Total energy – Kinetic energy = Potential energy and Total energy - Potential energy = Kinetic energy Main Menu Main Menu
Slide20: Mechanical work - the product of the force applied to an object along its direction of motion and the distance the object moves while the force is applied; Mechanical Work is done when a force or torque moves an object Work = Force x Distance W = F x D Work
Slide21: English unit of measure for work is foot-pound (ft-lb). SI unit of measure for work is Newton-meter (N-m) or joule (J). 1 joule = 1 Newton-meter
Slide22: Efficiency - a comparison of output work to input work. Output work - the work done by a machine to cause the load to move Input work - the work done by the force that causes the machine to operate
Slide23: Output Work %Efficiency = ------------------- x 100% Input Work
Slide24: Radian (rad.) - the angle formed between two radii drawn from the center of the circle to the edges of an arc on the circle where the arc is just equal in length of one radius; a unit of angle measure equal to 57.3 Pi (symbol ) - a mathematical constant with numeric value equal to 3.1416
Objectives: Objectives Define work done by torque. Define radian Explain relationship between work, torque applied and angle moved through Identify the effects of work done by torque Solve work problems given torque and angle information.
Work done by a Torque: Work done by a Torque Work = Torque Applied x Angle Moved Through W = T x Where: W = work T = torque = angle moved through
Slide27: Power – the rate of doing work Power = Work time 1 Horsepower = 550 ft lb/s
Slide28: Work Main Menu Main Menu Work is done on the books when they are being lifted, but no work is done on them when they are being held or carried horizontally.
Slide29: Energy Activities Main Menu The links provided will take you to several interactive sites where you will be expected to answer questions about energy, build roller coasters to specifications, and play games that involve providing the correct information to questions. Your teacher will instruct you on what to complete at each site. Amusement Park Physics Build a Coaster Energy Quiz Change Coaster Properties
Vocabulary List – Work in the Mechanical System: Vocabulary List – Work in the Mechanical System Technology(page3) Mechanical Work Joule Efficiency Radian Revolution Output Work Input Work Winch (page 28) Block and Tackle Foot pound Friction Newton meter Pi( ) Power