Topic Outcomes By the end of this topic you will: - have studied the different types of energy - be able to produce energy transfer flow diagrams - understand and use the principle of conservation of energy - understand and use new terminology

Energy transferred by electrical currents Electrical Energy Energy transferred by electrical currents

Energy of moving objects Kinetic Energy Energy of moving objects

Gravitational Potential Energy Energy due to an objects position in a gravitational field

Energy produced by nuclear reactions Nuclear Energy Energy produced by nuclear reactions

Energy produced by vibrating objects Sound Energy Energy produced by vibrating objects

Energy produced by radiant objects Light Energy Energy produced by radiant objects

Thermal Energy Energy produced by any object with a temperature above absolute zero (-273°C)

Elastic Potential Energy Energy stored in springy objects when squashed or stretched

Chemical Energy Energy stored in fuels (including food) that is released when chemical reactions occur.

Torch

Torch Chemical Energy Electrical Energy Light Energy

Torch Chemical Energy Electrical Energy Light Energy Heat Energy + Useful energy Wasted energy

Energy Transfer Circus Object Energy input Useful Energy output Wasted Energy Circus of transfer examples : cell and lamp, candle, nails in a tin, generator, motor, peltier cell (uses heat from warm water to create voltage), Kettle, solar panel on calculator, etc.

Fan heater

Hair Dryer

Car

Microphone

Food

Clock Work Toy

Drums

Nuclear Power Station

Bouncy Ball

How can we represent energy transfers? All the energy transfers (useful and wasted) that are associated with a device can be represented by a Sankey diagram. A Sankey diagram uses arrows to represent all the output energies. The thickness of each arrow is proportional to the amount of energy involved at that stage.

How can we represent energy transfers? 100 J electrical energy (input) 90 J heat energy (wasted) 10 J light (output) Filament light bulb

Energy efficient light bulb How can we represent energy transfers? 20 J electrical energy is supplied to the bulb, 10 J light energy is output. Calculate the wasted energy output What form is it in? Copy and complete the diagram. Energy efficient light bulb

Kinetic and Potential Energy How will the skydivers kinetic energy change during the fall? How will the skydivers potential energy change during the fall? What is the relationship between the two forms of energy?

𝐸 𝑃 =𝑚𝑔ℎ Gravitational Potential Energy The Equation for Gravitational Potential Energy (GPE) is 𝐸 𝑃 =𝑚𝑔ℎ Height Mass Gravitational Field Strength GPE [m] [kg] [J] [ g = 10 m/s2]

𝐸 𝐾 = 1 2 𝑚 𝑣 2 Kinetic Energy The Equation for Kinetic Energy is Velocity Mass [m/s] [J] [kg]