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Slide 1 / 111 Slide 2 / 111 Energy of Objects in Motion www.njctl.org Slide 3 / 111 Energy of Objects in Motion Click on the topic to go to that section · Energy and its Forms · Mechanical Energy · Energy of Motion · Stored Energy · Conservation of Energy · Types of Energy Resources Slide 4 / 111 Review from Last Unit Why does a force cause an object to accelerate? Answer In the previous units we have been studying the motion of objects. We talked about how far and fast an object goes if a force is applied to it. Slide 5 / 111 Energy and its Forms Return to Table of Contents Slide 6 / 111 What is Energy? Energy is a measurement of an object's ability to do work. How would you define work? How would you know if any work was being done? Slide 7 / 111 What is Energy? Energy is a measurement of an object's ability to do work. Work is defined as applying a force in order to move an object in a given direction. The more work that is done by an object, the more energy it exerts. Since energy is equal to work, the unit for both is the same, the Joule (J). 1 Joule = 1 Newton-meter Slide 8 / 111 Work Work can only be done to a system by an external force; a force from something that is not a part of the system. So let's say our system is a plane and the gate assistance vehicle. When the vehicle comes along and pushes back the plane, it increases the energy of the plane. The assistance truck is essentially doing work on the plane. Slide 9 / 111 Work The amount of work done is the change in the amount of energy that the system will experience. This is given by the equation: W = E final - Einitial · When a force is applied which causes the object to speed up and move a distance, the work is _______________. · If a resistive force was applied which caused the object to slow down over a distance, or not move at all, the work would be ____________. (think about acceleration) Slide 10 / 111 Positive Work If the object moves in the same direction as the direction of the force, the energy of the system is increased. The work is positive: W > 0. They can push the truck to get it to move! Slide 11 / 111 Negative Work If the object moves in the direction opposite the direction of the force then the work is negative: W < 0. The energy of the system is reduced. Pushing on the wall as hard as they can won't ever move the wall! Slide 12 / 111 Mechanical vs. Non-Mechanical Energy Energy exists in many forms, but can be broken down into two major forms: Mechanical Energy - The Energy of an object due to its motion and position. Mechanical Energy is the sum of the Kinetic and Potential Energy of an object. Mechanical Energy is usually used to describe a large object. Non-Mechanical Energy - The Energy of an object that is not due to it's motion or position. Non-Mechanical Energy usually describes an object at it's atomic level. Slide 13 / 111 1 Which of the following is the unit for energy? B Newton C Second D Joule Answer A Meter Slide 14 / 111 A positive B negative Answer 2 A wagon is rolling down a hill, a man tries to stop the wagon by trying to push it back up the hill but he is unsuccessful. Is the man doing positive or negative work? Slide 15 / 111 3 A boy kicks a soccer ball into a net. Did the boy do positive or negative work on the ball? B negative Answer A positive Slide 16 / 111 A positive B negative Answer 4 A woman walks across an icy sidewalk that has been covered in salt to help make it less slippery. Is the salt doing positive or negative work on the woman's shoes? Slide 17 / 111 Mechanical Energy Return to Table of Contents Slide 18 / 111 Forms of Mechanical Energy Mechanical Energy can be broken down into two different types of Energy: Energy of Motion, which is called Kinetic Energy and Stored Energy, which is called Potential Energy. Potential Energy has two forms, Gravitational and Elastic, depending upon how the Energy is stored. __________ Energy __________ Energy Write the underlined words into the correct place in the diagram. __________ Energy Slide 19 / 111 5 Which of the following is a form of Mechanical Energy? B Thermal C Chemical D Solar Answer A Kinetic Slide 20 / 111 Energy of Motion Return to Table of Contents Slide 21 / 111 6 Which of the following is a type of energy which is used to describe the motion of an object? B Nuclear Energy C Potential Energy D All of the above Answer A Electrical Energy Slide 22 / 111 Energy of Motion In order for an object to move, one of two scenarios has to occur: The object uses some of the potential energy that it had stored. The object is being given energy from an outside source. In either case, now that the object is in motion, the object is experiencing Kinetic Energy. Slide 23 / 111 Kinetic Energy An object's state of motion can be described by looking at the amount of kinetic energy that the object has at that moment in time. Since the state of motion of an object can change with time, the kinetic energy of an object can also change with time. Slide 24 / 111 Kinetic Energy The amount of Kinetic Energy that an object possesses is dependent on two factors: mass and velocity. Both of these factors are directly proportional to the kinetic energy. We talked about this mathematical relationship in the last chapter. What did directly proportional mean? Slide 25 / 111 Kinetic Energy, Mass, Velocity The larger the mass, the more energy is needed to move the object, therefore the _______________ the kinetic energy. Since kinetic energy is the energy of motion, the object has to have a velocity to have kinetic energy. The larger the velocity, the __________________ the kinetic energy. Slide 26 / 111 How Does Kinetic Energy Depend on Mass? If two identical objects are moving at the same velocity then they will have the same kinetic energy. If however, one object has more mass than the other while traveling at the same velocity, the heavier object will have more kinetic energy. v = 5 m/s v = 5 m/s A tennis ball and a bowling ball are both shown above. The bowling ball is heavier than the tennis ball. If they were both to move at the same velocity, which ball would have more kinetic energy? Slide 27 / 111 Velocity vs. Speed Remember that velocity is another way to measure motion. Simply put, velocity is the speed of an object with direction. Speed does not have a direction, so we call speed a scalar quantity. Since velocity has both magnitude and direction, it is a vector quantity. Runner's speed: 10 km/hr Runner's velocity: 10 km/hr to the East Slide 28 / 111 What is Kinetic Energy? In this picture, the hare is moving faster than the tortoise at this point. If we assumed that they had the same mass, who would have more kinetic energy? Why? Discuss this with a partner. Slide 29 / 111 How Does Kinetic Energy Depend upon Velocity? If two identical objects are moving at the same velocity then they will have the same kinetic energy. If however, one of the object's is moving faster, the one which is moving faster will have more kinetic energy. v = 5 m/s v = 10 m/s In the diagram above, two identical tennis balls are moving. Which tennis ball has more kinetic energy and why? Slide 30 / 111 A a police car B an ambulance C a Firetruck D they all have the same kinetic energy Answer 7 Three different emergency vehicles are noticed driving on the highway at a speed of 25 m/s. Which of the following cars have the most kinetic energy at that moment? Slide 31 / 111 A a little league pitcher B a high school pitcher C a major league pitcher D they all had the same kinetic energy Answer 8 Three different baseball pitchers had the speed of their fastball measured by a radar gun. Which of the following pitcher's fastball had the smallest amount of kinetic energy? Slide 32 / 111 9 Which of the following situations has the lowest kinetic energy? Be ready to explain your answer. B a child riding a bike C a woman driving a car D it is impossible to tell Answer A a man sitting on a park bench Slide 33 / 111 Calculating Kinetic Energy Kinetic Energy can be solved for by using the equation: KE = 1 2 mv2 Fill in the table below. Name variable units Kinetic Energy m m/s Slide 34 / 111 Example - Calculating Kinetic Energy 1 KE = 2 mv2 KE = (0.5)(1000 kg)(5 m/s)2 KE = (0.5)(1000 kg)(25 m2/s2) KE = 125,000 J Teacher Notes A car, which has a mass of 1,000 kg, is moving with a velocity of 5 m/s. How much Kinetic Energy does the car possess? Slide 35 / 111 Answer 10 A 10 kg snowball is rolling down a hill. Just before reaching the bottom, it's velocity is measured to be 10 m/s. What is the Kinetic Energy of the ball at this position? Slide 36 / 111 Answer 11 A 100 kg man running back in football is running with a velocity of 2 m/s. What is his Kinetic Energy? Slide 37 / 111 Answer 12 A 2000 kg car with a velocity of 20 m/s slows down and stops at a red light. What is the change in Kinetic Energy? Slide 38 / 111 Answer 13 A 50kg girl rode her 12 kg bicycle in a race. She started from rest and peddled with a velocity of 10 m/s. What is the change in Kinetic Energy of the girl and her bicycle? Slide 39 / 111 Thinking Mathematically KE = 1 mv2 2 We have already said that mass and velocity are directly proportional to kinetic energy. This means that if the mass of the object doubles, the kinetic energy ___________. If the mass of the object increases by a factor of 5, then the kinetic energy___________ by ______________. If the mass of the object decreases by half, then the kinetic energy will ____________ by ___________. Slide 40 / 111 Thinking Mathematically Kinetic Energy can be solved by using the equation: KE = 1 mv2 2 Looking at this equation again, we can see that the kinetic energy is also directly proportional to the square of the velocity. This means that if the velocity doubles, the kinetic energy increases by a factor of 4. 22=4 If the velocity is quadrupled, then the kinetic energy increases by a factor of 16. 42= 16 Slide 41 / 111 Answer 14 If the mass of a wagon is doubled, by what factor does the KE increase? Slide 42 / 111 Answer 15 If the velocity of a wagon is tripled, by what factor does the KE increase? Slide 43 / 111 Answer 16 Two balls are moving with the same velocity, ball A has a mass of 10kg and ball B has a mass of 40kg. How much more KE does ball B have? Slide 44 / 111 Stored Energy Return to Table of Contents Slide 45 / 111 Where does Kinetic Energy Come From? Imagine a roller coaster car that is at the top of the first hill and is stopped. Does the car stay stopped at the top of the hill for the entire ride? What happens? Slide 46 / 111 Where does Kinetic Energy Come From? Once the car leans over the edge, gravity pulls it down. The ride is taking advantage of the gravitational attraction between the car and Earth to give the car kinetic energy and make it go faster as it falls. The kinetic energy the car is receiving is coming from another type of energy called Potential Energy. Slide 47 / 111 Where does Kinetic Energy Come From? Potential Energy is energy that an object has stored within it due to it's position, in this case, the car's height. There are two forms of Potential Energy that we will be looking at in this unit: Gravitational Potential Energy and Elastic Potential Energy Slide 48 / 111 Gravitational Potential Energy An object has a certain amount of energy naturally associated with it. If the object has a force acting on it from a distance (like gravity) and there is no object supporting the object, then the amount of energy that the object has is called the Gravitational Potential Energy. This energy is stored energy and means that it can be used at a later time to cause an object to move. Slide 49 / 111 Gravitational Potential Energy Gravitational Potential Energy is determined by three factors: mass, gravity, and height. All three factors are directly proportional to energy. Mass: The heavier the object is, the _______ gravitational potential energy the object has. Gravity: The larger the gravity, the _________ gravitational potential energy the object has. Since gravity on Earth is considered a constant, this will not change. Height: The higher the object is off the ground, the _________ gravitational potential energy the object has. Slide 50 / 111 How Does Mass Affect Gravitational Potential Energy In this picture, the mass of a tennis ball was doubled when it was at the same height off of the ground. m = 2 kg h=2m m = 1 kg h=2m How does the gravitational potential energy compare for the two objects? Slide 51 / 111 How Does Mass Affect Gravitational Potential Energy m = 2 kg m = 1 kg mass: double = doubled gravity: stayed the same = no change h=2m h=2m height: stayed the same = no change Since the only thing that changed was the mass, which doubled, the gravitational potential energy also doubled. Slide 52 / 111 How Does Height Affect Gravitational Potential Energy In this picture, the same object, a tennis ball, is lifted to a height that is twice as high. How would the Gravitational Potential Energy compare at the higher height? h=4m h=2m Slide 53 / 111 How Does Height Affect Gravitational Potential Energy mass: stayed the same = no change gravity: stayed the same = no change height: doubled = doubled h=4m h=2m Since the only thing that changed was the height which doubled, the gravitational potential energy also doubled. Slide 54 / 111 A they are the same B twice as large C ten times as large D thirty times as large Answer 17 A bowling ball which has a mass that is 30 times larger than a softball, is lifted to the same height as the softball. How much larger is the Gravitational Potential Energy for the bowling ball compared to the softball? Slide 55 / 111 18 Two balloons are floating in the sky. If one balloon is floating at a height of 30 m and the other, identical balloon, is floating at a height of 45 m, how much larger is the Gravitational Potential Energy of the higher balloon compared to the lower one? B they are the same C 1.5 times larger D twice as large Answer A half as large Slide 56 / 111 Calculating Gravitational Potential Energy Gravitational Potential Energy can be solved by using the equation: GPE = mgh Name Gravitational Potential Energy Gravity variable m units m Slide 57 / 111 Example - Calculating Gravitational Potential Energy A basketball, whose mass is 0.5 kg, is held at a height of 2 m above the ground. How much Gravitational Potential Energy does the basketball possess? GPE = mgh GPE = (0.5 kg)(9.8 m/s2)(2 m) GPE = 9.8 J Slide 58 / 111 Answer 19 A 50 kg diver is standing on top of the 10 m platform. How much Gravitational Potential Energy does he have? Slide 59 / 111 Answer 20 A 3,000 kg hot air balloon is hovering at a height of 100 m above Earth's surface. How much Gravitational Potential Energy does it possess? Slide 60 / 111 Thinking Mathematically GPE = mgh GPE = mgh We know that GPE is directly proportional to mass, to gravity, and to height. This means that as any of these increase, the GPE increases by the same factor. If any of these decrease, then the GPE decreases by the same factor. Slide 61 / 111 Answer 21 A ball is dropped from 30m, it is then dropped from 60m. By what factor does the GPE increase? Slide 62 / 111 22 A 3kg object and a 9kg object are both dropped from the same height. Which has more GPE? Answer A 3kg object B 9kg object Slide 63 / 111 Answer 23 A 3kg object and a 9kg object are dropped from the same height. How much less is the GPE of the 3kg object than the 9kg object? Slide 64 / 111 Elastic Potential Energy Sometimes it is not possible to take advantage of gravity's pull on an object to change it's Kinetic Energy, such as if the object is on a flat surface. One type of Potential Energy is called Elastic Potential Energy. Looking at the picture to the right, can you come up with an idea about what Elastic Potential Energy is? Slide 65 / 111 Elastic Potential Energy Elastic Potential Energy is determined by two factors: the elasticity of the material and how far it is stretched or compressed. Think about what you know about rubber bands. Do you think elasticity and distance stretched are directly proportional or indirectly proportional to the energy? Talk about this at your table. Slide 66 / 111 Elastic Potential Energy Elasticity: The more elastic that a material is, the more elastic potential energy the object has. Distance of stretch (or compression): The larger the distance of the elastic material is stretched (or compressed) the more elastic potential energy it has. Slide 67 / 111 What is the Difference Between Stretching and Compression in a Spring Think about a slinky sitting on a desk. A spring has no potential energy stored in it if it is neither stretched nor compressed. This distance, as shown in figure (a) is called the relaxed length. Stretching a spring is caused when the spring is pulled increasing the length of the spring compared to the relaxed length, as shown in figure (b). (a) (b) (c) Slide 68 / 111 What is the Difference Between Stretching and Compression in a Spring Compressing a spring is caused when the spring is squeezed which causes a decrease in the length of the spring compared to the relaxed length, as shown in figure (c). In this diagram, both figures (b) and (c) would have the same elastic potential energy because both springs are displaced the same distance, x. (a) (b) (c) Slide 69 / 111 How Does Elastic Potential Energy Depend Upon Compression In the diagram to the right, both pictures show a spring, which is an elastic material. In the top picture however, the spring is not stretched or compressed, and therefore there is no potential energy stored in the spring. In the bottom picture, the spring is compressed and therefore elastic potential energy is stored in the spring. Slide 70 / 111 A When she is standing on the trampoline B When she is in the air C When she lands on the trampoline after jumping D she will always have the same elastic potential energy Answer 24 A child jumps on a trampoline in his backyard. At which of the following will she have more elastic potential energy? Slide 71 / 111 Calculating Elastic Potential Energy Elastic Potential Energy can be solved by using the equation: EPE = 1 kx2 2 EPE = Elastic Potential Energy (J) k = spring constant (N/m) x = distance of stretch or compression (m) Slide 72 / 111 Spring Constant 1 2 EPE = kx 2 The energy and distance variables in this equation are likely familiar. But what is the spring constant (k)? Look at the two springs to the right. Which would be easier to stretch? Every spring has a different degree of stretchiness and that is what the spring constant represents. Slide 73 / 111 Spring Constant 1 2 EPE = kx 2 Breaking down the units for spring constant also explains what the variable represents. Can you explain what Newtons per Meter (N/m) means? Slide 74 / 111 Example - Calculating Elastic Potential Energy EPE = 12 kx2 EPE = ( 12 )(10 N/m)(1 m)2 EPE = ( 1 )(10 N/m)(1 m2) 2 EPE = (5 N*m) EPE = 5 J Teacher Notes A spring, which has a spring constant of 10 N/m, is stretched a distance of 1 m. How much Elastic Potential Energy is stored in the spring? Slide 75 / 111 Answer 25 A child bouncing on a pogo stick compresses the spring by 0.25 m. If the spring constant of the spring on the bottom of the pogo stick is 200 N/m, what is the Elastic Potential Energy stored in the spring when it is compressed? Slide 76 / 111 Answer 26 A rubber band with a spring constant of 40 N/m is pulled back 0.5 m. How much Elastic Potential Energy is stored in the elastic band? Slide 77 / 111 27 Which of the following would you expect to have the smallest spring constant? B a slinky C a spring in a pen D a trampoline spring Answer A a garage door spring Slide 78 / 111 Thinking Mathematically EPE = 1 2 kx 2 1 KE = 2 mv2 Notice that the equation for EPE is similar to the equation for KE. Remember that in the equation for KE, energy was directly proportional to the mass and it was also directly proportional to the square of the velocity. What do you think the relationship is between EPE and the spring constant? What do you think is the relationship between EPE and the distance the spring is stretched or compressed? Slide 79 / 111 Thinking Mathematically EPE = 1 2 kx 2 EPE is _________________________ to the spring constant. EPE is _________________________ to the square of the distance the spring is compressed or stretched. Slide 80 / 111 Answer 28 If the spring constant is tripled, by what factor does the EPE increase? Slide 81 / 111 Answer 29 If the spring constant is halved, by what factor does the EPE decrease? Slide 82 / 111 Answer 30 If the distance a spring is stretched is increased by a factor of 6, by what factor is the EPE increased? Slide 83 / 111 Conservation of Energy Return to Table of Contents Slide 84 / 111 Conservation of Energy What we have looked at so far is that an object has Kinetic Energy if the object is in motion. The faster that the object is going, the more Kinetic Energy it has. In order for an object's Kinetic Energy to increase, it must get more energy from somewhere. But where would it get that energy? Hint: think back to the roller coaster. What kind of energy did it have at the top of the hill? Slide 85 / 111 Conservation of Energy In order for an object's Kinetic Energy to increase, it must take Energy from it's stored energy, which we call Potential Energy. When this happens, the Potential Energy that an object possesses decreases. When this happens, the Total Energy (TE) in that closed system contains does not change. This is called the Conservation of Energy. TEi = TEf i = initial f= final Slide 86 / 111 Conservation of Energy If the amount of energy that we start with "Ei" and the amount we end up with as "Ef" then we would say that if no energy is added to or taken away from a system. TEi = TEf When looking at the Mechanical Energy, the total energy possible is the Potential Energy (PE) and the Kinetic Energy (KE) added together. (PE + KE)i = (PE + KE)f Slide 87 / 111 Conservation of Energy (PE + KE)i = (PE + KE)f If any object at any height is being supported, then the Gravitational Potential Energy is 0 J. If a spring is not stretched or compressed, then the Elastic Potential Energy is 0 J. If the object is not moving at any position, then the Kinetic Energy is 0 J. Slide 88 / 111 What is Meant by a Closed System? A closed system involves only the material that is being measured. Everything else is called the surroundings. In the diagram of the ball falling shown to the right, the ball and Earth make up the system as the Gravitational Potential Energy that is stored in the ball due to it's height from Earth's surface is transferred to Kinetic Energy as the ball falls. Slide 89 / 111 What If Both Types of Mechanical Energy Are Present at the Same Location? In the case when an object is moving at some height above the ground, the object has both Gravitational Potential Energy and Kinetic Energy are present. Using the transfer of mechanical energy equation, the totalenergy at that position is the sum of the two individual energies. (PE + KE) Slide 90 / 111 At position A in the diagram below, the roller coaster car has 40 J of Total Energy and has a velocity equal to 0 m/s. How much Kinetic Energy does the car possess at Point A? 0J How much Gravitational Potential Energy does the car possess at Point A? 40 J 40 J 15 J 25 J Slide 91 / 111 At position B in the diagram below, the roller coaster car has a Gravitational Potential Energy equal to 15 J. How much Total Energy does the car possess at Point B? 40 J How much Kinetic Energy does the car possess at Point B? 25 J 40 J 15 J 25 J Slide 92 / 111 At position C in the diagram below, the roller coaster car has a Gravitational Potential Energy equal to 25 J. How much Total Energy does the car possess at Point C? 40 J How much Kinetic Energy does the car possess at Point C? 15 J 40 J 15 J 25 J Slide 93 / 111 31 At what position in the diagram below does the object have only Gravitational Potential Energy? A W X Answer B C Y D Z E None of the above h=0m Slide 94 / 111 32 At what position in the diagram below does the object have only Kinetic Energy? A W X Answer B C Y D Z E None of the above h=0m Slide 95 / 111 Answer 33 At what position in the diagram below does the object have only Gravitational Potential and Kinetic Energy? A W B X C Y D Z E None of the above h=0m Slide 96 / 111 Transfer of Kinetic Energy to Elastic Potential Energy Kinetic Energy can be transferred into Potential Energy the same way. What must be true is that the Total Energy of the object must be always the same. Slide 97 / 111 Transfer of Kinetic Energy to Elastic Potential Energy In the top picture, the block is travelling at 10 m/s, meaning that it has Kinetic Energy. Because the spring is at the relaxed length there is no Elastic Potential Energy present. All of the block's energy is Kinetic Energy. In the bottom picture, the block has compressed the spring and is no longer moving, meaning the block has no Kinetic Energy. All of the Kinetic Energy has been transformed into Elastic Potential Energy. Slide 98 / 111 Answer 34 In which position of the block would the system have only EPE? A B C Slide 99 / 111 Answer 35 In which position of the block would the system have only KE? A B C Slide 100 / 111 A B C Answer 36 In which position of the block would the system have both KE and EPE? Slide 101 / 111 What if the Total Mechanical Energy is not equal at the beginning and the end? If the total amount of energy that we start with, Ei, does not equal the total amount of energy that we end up with, "Ef ", then mechanical energy is not naturally conserved. TEi = TEf Because of this, the system is not a closed system, and the surroundings are allowed to interact with the system. This means that there is an outside for that is acting on the system over some distance. We talked about this in the last unit. What term did we use for the energy used when a force acts over a distance? Slide 102 / 111 Types of Energy Resources Return to Table of Contents Slide 103 / 111 Energy Resources Electrical Energy can be produced through the Conservation of Energy by using the Mechanical Energy contained in Energy Resources. Energy Resources can be broken down into two categories: Renewable and Non-Renewable. Renewable Energy Resources are natural resources that can replenish themselves over time. Non-Renewable Energy Resources are natural energy resources that exist in limited supply and cannot be replenished in a timely manner. Slide 104 / 111 Types of Energy Resources Slide 105 / 111 Energy Production from the Sun Solar Energy is a renewable form of energy that is produced when photons that are contained in sunlight are absorbed by specially designed plates that are angled towards the sun. When the photons hit the solar panels, charged particles are free to move which causes a current to be produced. This current is converted to usable electricity by the home. Slide 106 / 111 Energy Production from the Wind Wind is a renewable energy resource that is used to create electricity by wind turbines, such as in the Alta Wind Energy Center in California, the world's largest Wind farm. As the wind blows past the blades of the turbine, the Kinetic Energy of the wind is transferred to the blades of a Wind Turbine as they rotate. Inside the column of the turbine there is a drive shaft which is connected to a generator. As the blades spin, the drive shaft converts the kinetic energy into mechanical energy. A generator that is connected to the drive shaft then converts the mechanical energy into electrical energy. Slide 107 / 111 Energy Production From Water Water is a renewable resource that can be used to create electricity in dams such as the Hoover Dam. Dams are used to convert the kinetic energy possessed by moving water into electricity by moving a turbine connected to a generator. Slide 108 / 111 Energy Production From Water The water at the top of the reservoir possesses Gravitational Potential Energy. As the water moves through intake and down the penstock, the water's Gravitational Potential Energy is converted into Kinetic Energy. As the water moves past the turbine, the Kinetic Energy that the water possesses is converted into Mechanical Energy as the turbine moves. The Mechanical Energy that is created by the turbine is then transformed into Electrical Energy by the generator. Slide 109 / 111 Energy Production from Fossil Fuels Fossil Fuels are a non-renewable energy resource that can be used to produce electricity when it is burned. Fossil Fuels include: Natural Gas, Oil, and Coal (shown to the right). When the fuel is burned the heat turns water into steam which turn the blades of turbine producing energy similar to the way that energy is produced in a hydroelectric dam. Slide 110 / 111 Effects of Using Fossil Fuels As An Energy Resource Fossil Fuels are Non-Renewable Energy Resources due to how long it takes for them to be produced compared to how much is used to create energy. Fossil Fuels take millions of years to be produced. Fossil Fuels are also not considered "Clean" Energy resources as they produce Carbon Dioxide (CO2) when burned. Carbon Dioxide is considered a Greenhouse Gas, which many believe is a cause Global Warming. Slide 111 / 111 37 Which of the following is not considered a renewable energy resource? B Wind C Hydroelectric D Fossil Fuels Answer A Solar