Explore Exploration Activity More important than knowing what energy is, is understanding how it PE -10000J behaves/transforms. Every process or change that occurs in nature can be analyzed in terms of a transformation of energy from one form to another. The study of various forms of energy and the transformations from one form into another led to one of the greatest generalizations in physics, the law of conservation of energy. PE= 7500 3 The law of conservation of energy KE - 2500J Energy cannot be created nor destroyed. It can be transformed from one form into another, but the total amount of energy never changes PE-5000J KE-50003 PE . KE KE When you consider any system in its entirety, whether it is as simple as a swinging pendulum or as complex as an exploding galaxy, there is one quantity that does not change: energy. It may change form or it may be transferred from PE 25003 KE . 7500) one place to another, but the total energy score stays the same. When analyzing the conservation of energy, ignore forms of energy that have a negligible influence or are not relevant. When ignoring these forms of energy mechanical energy is defined as the sum of kinetic energy and all forms of potential energy. ME = KE + EPE APERO KE=100003 ME Mechanical energy in joules KE Kinetic energy in joules EPE The sum of all potential energy in joules In the absence of friction, total mechanical energy remains the same. This principle is called the conservation of mechanical energy. For example, take a look at the lady leaping from the burning building. Her initial mechanical energy at the top of the building is equal to her final mechanical energy at the bottom of the building. LEARN 4 LIFE CHANGE LIVES Integrated Science 1B Credit 3ME; = MEf ME, Initial mechanical energy Final mechanical energy MEr Adapted from Hewitt, Paul G. Conceptual Physics. Upper Saddle River, NJ: Prentice Hall, 2006. Print. Use the information above to answer the following questions. Make sure to show your work. 1. According to the picture on the previous page, what is the initial mechanical energy of the woman falling from the building? What is her final mechanical energy? 2. What is the woman's kinetic energy when her potential energy is 2500 joules? 3. What is the woman's potential energy when her kinetic energy is 1000 joules? 4. If the woman was wearing a parachute how do you think that might affect her kinetic energy? Would the mechanical energy of the system change? Explain your answer. EARN 4LIFE CHANGE LIVES Integrated Science 1B Credit 3