Energy - 1st Year Science - PDF

Energy 1st Year Science MS. MAYNE Energy: The ability to do work James Joule: He was a famous scientist born in 1818 He spent his time studying the different types of energy & energy conversions. Unit of energy: ______________ 8 Types of Energy: Energy comes in many forms, lets examin...

Energy 1st Year Science MS. MAYNE Energy: The ability to do work James Joule: He was a famous scientist born in 1818 He spent his time studying the different types of energy & energy conversions. Unit of energy: ______________ 8 Types of Energy: Energy comes in many forms, lets examine the main forms of energy. Heat energy Potential energy Electrical energy Kinetic energy Chemical energy Sound energy Light energy Nuclear energy Potential Energy: The energy an object has due to its position or shape. Examples: Gravitational Potential 1. A car on the top of a hill. 2. A drawn bow & arrow. 3. A stretched spring/rubber band. Elastic Potential Kinetic Energy: The energy of an object that is in motion. Aka ‘mechanical energy’. Examples: 1. Walking/running. 2. Throwing a ball. 3. A moving car. Chemical Energy: Energy stored in the chemical bonds of atoms and molecules. Examples: 1. Food. 2. Fuel e.g. coal and oil. 3. Batteries Light Energy: Sunlight is the most important source of light energy on Earth. Light from the sun provides the energy required for plants to grow (photosynthesis). E.g. Light Bulb, Sun, TV screen. Heat Energy: When energy is given to an object the temperature of the object may increase. Examples: 1. The sun 2. A fire 3. An oven.  Electrical Energy: Electrical energy is delivered by tiny, charged particles called electrons. A wire carrying electricity can be used to supply energy to machines etc. Examples: 1. A power outlet. 2. Lightning (electrical field within a storm)  Sound Energy: Sound energy is a form of kinetic energy created when objects vibrate. This makes the air around the object vibrate and causes our eardrums to vibrate – allowing us to hear.  Nuclear Energy: The nucleus of an atom has an enormous amount of stored energy. When the nucleus is smashed or changed, the atom can release this energy. Examples: 1. Nuclear bombs. 2. Nuclear power plants: heat water to produce steam. This steam is  Fill in the blank: Energy Edition P _____________________ energy C__________________________energy H__________________________ energy E__________________________ energy K__________________________ energy L__________________________ energy S__________________________ energy N__________________________ energy  Energy Conversions Conversion Energy Conversions: He measured the temperature of water at the top and bottom of a waterfall while on honeymoon with his wife. He found that the potential energy of the water on the top of the water was converted into heat energy when it fell over the waterfall.  Energy Conversions: Think of all the ways electricity is used in your home… Washing machine = kinetic TV = sound and light Kettle = heat The principle of conservation of energy: Energy cannot be created or destroyed, but can only be changed/converted from one form to another. Energy Conversions:  Energy Conversions: 🡪 Chemical Energy Kinetic Energy Stations: 1. Energy stick. 2. Music player. 3. Pink stick. 4. Slinky. 5. Lights.  Energy Dissipation: When converting energy from one form to another, some energy is wasted / dissipated. Energy dissipation is the conversion of energy to a form that is less useful. Energy Efficiency: The bulb on the right is supplied with 100 J of electrical energy but only 2 J are converted to light energy. The rest is dissipated (wasted) as heat energy. Energy Efficiency: Note – the total amount of energy entering the bulb is equal to the total energy leaving the bulb. Therefore energy is conserved. Sankey Diagrams: Energy flow can be shown more clearly using a Sankey diagram. The image below shows the energy entering and leaving a device.  The straight line Sankey Diagrams: shows the amount of energy used for the This line purpose intended. represents the total energy entering the appliance per second. The down-facing arrow shows the amount of energy dissipated. Note - The thickness of the arrow represents the amount of energy being used. Calculating Energy Efficiency: Calculate the percentage energy efficiency of each bulb from the Sankey diagram: Electrical energy (100 joules) Light energy (2 joules) Heat energy (2 joules) A Filament Light Bulb Step 1: Write the formula Step 2: Fill in the equation Step 3: Write the answer with the correct unit Calculate the percentage energy efficiency of each bulb from the Sankey diagram: Electrical energy (4 joules) Light energy (0.8 joules) Heat energy (3.2 joules) An LED Light Bulb Step 1: Write the formula Step 2: Fill in the equation Step 3: Write the answer with the correct unit Energy Efficiency: The EU made it law that products must display an energy rating from A-G when being offered for sale. The higher the classification on the scale the more efficient the appliance is. Sources of Energy: Our sources of energy can be classified into two categories - Renewable and Non-Renewable. A renewable energy source will never be used up. A non-renewable energy source will not be regenerated in our lifetime. Renewable Sources of Energy: Wind energy Solar energy Hydroelectricity Biomass Wave energy Tidal energy Geothermal energy Renewable Energy: A renewable energy source will never be used up. Advantage: Renewable sources produce no harmful waste products e.g. CO2. Disadvantage: Expensive to install/set up. Non-Renewable Sources of Energy: Fossil fuels Nuclear fission. Non-Renewable Energy: A non-renewable energy source will not be regenerated in our lifetime. Fossil Fuels: Advantage: Easy to transport and store. Relatively cheap. Disadvantage: Produce harmful waste products e.g. CO2 Sustainable Energy Usage: Sustainability is the use of a resource so that it does not run out. When using energy sustainably, it should: 1. Not damage the environment. 2. Be available for many future generations. 3. Be available at a reasonable cost. Sustainable Energy Usage: 1. Replace burning fossil fuels with renewable energy sources. 2. Use energy efficient appliances where possible. 3. Reduce energy wastage (energy conservation) e.g. Switching off lights. Walk, cycle or use public transport instead of a car. Calculating Energy Use: Work = Force (in newtons) x Distance (in metres) Calculating Energy Use: Calculating Energy Use: Energy Worksheet Qs: