Energy hank Energy Videos bill Nye http www

Energy hank

Energy Videos: bill Nye • http: //www. youtube. com/watch? v=z. TXW 9 a. RO 23 Y • http: //www. youtube. com/watch? v=Vfcsq 6 yl. Rzg • http: //www. youtube. com/watch? v=Xk. DG 02 nzf. Sk

What is energy? ? • Difficult to define because you usually can’t see it and… • Energy: the ability of an object to produce a change in itself or the world around it OR the ability to do work

The law of the conservation of energy • Law of conservation of energy: Energy cannot be created or destroyed • It can only be transferred from one form to another • conservation of energy

Mechanical energy 1. Mechanical energy: the energy of moving objects

Sound energy 2. Sound energy: the energy from the vibration of particles in a medium

Chemical energy 3. Chemical Energy: energy that is stored in the chemical composition of matter • Stored inside the bonds of living or once things

Electrical energy 4. Electrical energy: the energy caused by electrons moving • Electricity has to have a conductor to flow through

Light energy 5. Electromagnetic (light) Energy: energy that is transmitted through light waves • Does not have to have a medium • Can travel through space • Comes in many forms that we cannot see • Examples: sunlight, light bulb, microwave, ultraviolet light

Heat energy 6. Thermal Energy: energy from the movement of particles in matter All particles in all matter is constantly moving

Nuclear energy 7. Nuclear energy: the energy holding the nucleus of an atom together Examples: nuclear power plant, fusion on the surface of the sun

Converting mass into energy • Nuclear Fission: when a large atom splits apart to make 2 smaller atoms • A small amount of mass is converted to a large amount of energy •

Nuclear energy • Nuclear Fusion: when 2 smaller atoms fuse together to make one larger atom • Energy is released • bill nye energy

The human body • Energy conversions in your body: Energy from the food we eat is converted into the energy we use to move and keep warm • Calorie (C) is a unit used to measure how much energy is in the food we eat • 1 Calorie = 4184 Joules of energy • Fats = 9 Calories/gram • Carbohydrates = 4 Calories/gram • Proteins = 4 Calories/gram

Transforming Energy • Transforming chemical Energy: the energy in the chemical bonds of matter can be transformed into different types of energy

Transforming Energy • Transforming Electrical Energy: electrical energy can be transformed into many different forms to suit our needs

Transforming Energy • Transforming mechanical energy: mechanical energy can be transferred to another object to move it or stored as electricity

Transforming Energy • Transforming nuclear energy: nuclear energy can be transformed into electricity for our homes and businesses

Converting nuclear energy • what is nuclear energy? • how does nuclear power work?

Transforming Energy • Transforming thermal energy: thermal energy can be converted into light energy and is used to cook and heat things • marshmallows

Transforming Energy • Transforming electromagnetic energy: electromagnetic energy can be transformed into thermal, electrical and chemical energy

Transforming Energy • Transforming sound energy: sound energy can be transformed into mechanical energy and electrical energy

Mechanical Energy • Mechanical Energy: the total amount of potential energy and kinetic energy in a system • Equation: ME = PE + KE • ME = mechanical energy (energy of motion) • PE = potential energy (stored energy) • KE = kinetic energy (moving energy)

Kinetic energy • Kinetic energy: the energy of a moving object because it is in motion • Depends on: 1. Mass of the object 2. Speed of the object

Kinetic energy equation m = mass V = velocity Measured in Joules (J)

example • A jogger whose mass is 60 kg is moving at a speed of 3 m/s. What is the kinetic energy of the jogger? • E = (1/2)(60 kg)(3 m/s)² • E = (1/2)(60)(9) = 270 J

Potential energy • Potential energy: stored energy due to the objects position • kinetic/potential energy • kinetic vs potential energy

Elastic Potential energy • Elastic potential energy: energy stored by something that can be stretched or compressed • Ex: rubber band, bow

Chemical potential energy • Chemical potential energy: energy stored in the chemical bonds of matter • Ex: fireworks, fuel, food, bomb, wood

Gravitational potential energy • Gravitational potential energy (GPE): energy stored by an object due to its position relative to the ground • Equation: GPE = mgh • m = mass of object • g = 9. 8 m/s² • h = height above the ground

example • What is the gravitational potential energy of a ceiling fan that has a mass of 7 kg and is 4 meters above the ground? • GPE = (7 kg)(9. 8 m/s²)(4 m) • GPE = 274 J

Changing gravitational potential energy • How can we change the GPE of an object? 1. Lift it higher off the ground 2. Increase its mass

Kinetic vs. potential energy • roller coaster

Energy conservation and friction • When an object moves and friction affects it, the friction causes some of that energy to be converted into heat

Energy and friction • Name 3 different examples of friction converting energy into heat