2 Unit Two: Work and Energy Chapter 5 Work, Energy and Power5.1 Work5.2 Energy Conservation5.3 Energy Transformations
3 Chapter 5 Learning Goals Calculate the amount of work done by a simple machine.Use units of joules to measure the amount of work done.Analyze the effects of changing force or distance in a simple machine.Calculate the efficiency of a machine.Calculate power in machines.Discuss perpetual motion machines.
4 Chapter 5 Vocabulary Terms chemical energyelectrical energyenergy transformationsheat efficiencyhorsepowerjoule energykinetic energylaw of conservation of energynuclear energypotential energy wattpower workradiant energyradiationsolar power
5 5.1 WorkForce (N)Work (joules)W = F x dDistance (m)
9 5.2 Energy Energy is the ability to do work. Any object that has energy has the ability to create force.Energy is measured in the same units as work.A joule is a unit of force that acts over a distance.
10 5.2 Potential Energy Ep = mgh Mass (kg) Potential Energy (joules) Height (m)Accelerationof gravity (m/sec2)
11 5.2 Kinetic Energy Ek = 1 mv2 2 Mass (kg) Kinetic Energy Speed (m/sec) (joules)Ek = 1 mv22Speed (m/sec)
12 5.2 Energy Conservation What is energy and how does it behave? Key Question:What is energy and how does it behave?*Read text section 5.2 BEFORE Investigation 5.2
13 5.3 Energy Transformations Energy transformations occur between different types of energy.radiant energyelectrical energychemical energynuclear energy
14 Energy Transformations in a Power Plant Power plants convert chemical energy into electrical energy.chemical energyheat energymechanical energyelectrical energy