<p> Introduction to Energy Study Guide – Part 1</p><p>1. What is energy?</p><p>The ability to do work</p><p>2. What is kinetic energy?</p><p>The energy of motion (movement)</p><p>3. Can objects with kinetic energy do work? Give an example. </p><p>Yes. If you swing a hammer, you can do the work of driving a nail into a board.</p><p>4. What two things does kinetic energy depend on (in other words, what two things do you need to know to calculate kinetic energy?)</p><p>The object’s mass and its speed. Speed is the more important one of the two.</p><p>5. If two bicycles have the same mass, but one is traveling at 10 m/s and the other is traveling at 15 m/s, which has more kinetic energy?</p><p>The faster one</p><p>6. If two people are running at the same speed, but one has a mass of 60 kg and the other has a mass of 75 kg, which has more kinetic energy?</p><p>The more massive one</p><p>7. What is potential energy?</p><p>Potential energy is stored energy 8. What does it mean when we say potential energy depends on the height of the object? Give an example and illustrate it.</p><p>Gravitational potential energy is the energy something has because of its height above the earth. A can of beans, dropping from 200 feet, will hit with more force, because it had more energy than a can of beans dropping from 6 inches. </p><p>9. What does it mean when we say potential energy depends on the shape of an object? Give an example.</p><p>If you do work on an object so that the shape changes, you can give it potential energy. For instance, when you pull back the string of a bow, you do work on it to change its shape. The energy you used is transferred to the bow, stored there, and then used to give energy to the arrow.</p><p>10. At which point does this pendulum have the most KE?</p><p>At which point does the pendulum have the most PE? Point #1</p><p>At point 4, what is happening to the KE and PE?</p><p>At point 4, the PE is increasing, while the KE is decreasing 11.Draw a pendulum, and show how the potential energy and kinetic energy change as it swings.</p><p>1. Highest potential energy when you first let it go.</p><p>3. At the other side, the potential energy is high again, and the kinetic is low. +KE -KE - PE +PE</p><p>2. When the pendulum hits the middle, its KE is at its highest.</p><p>12. What is an energy conversion?</p><p>A change from one form of energy to another.</p><p>13.Show how we would use symbols to describe the energy conversions that take place in the following machines:</p><p> mechanical alarm clock electrical light</p><p> sound thermal</p><p> battery chemical electrical thermal light bulb electrical light</p><p> thermal</p><p> mechanical thermal blender electrical kinetic</p><p> sound</p><p>14.What is the law of conservation of energy?</p><p>Says that energy can neither be created nor destroyed. It just gets converted from one form to another.</p><p>15.Whenever an energy conversion takes place, one form of energy is always created. What form is that?</p><p>Thermal energy is produced with every conversion.</p><p>16.Where does the thermal energy from energy conversions go?</p><p>Most of it goes into the air.</p><p>17.Is it possible to have a machine that keeps moving forever without any source of energy? Why or why not?</p><p>No, because, remember, energy cannot be created. Therefore, every machine in the world has to have some source of energy.</p>