HS Student Handout Conservation Energy NGSS .docx Instruction to Laboratory Online Activity. Conservation of Energy at the Skate Park XXXXXXXXXXName:___________ Learning Objective: To investigate the...

Its only 15 questions to answer. I am working on another assignment and don't have time to finish this short answer and questions homework assignment that is due today at 8:30 pm. Interactive lab exercise is at https://phet.colorado.edu/en/simulation/energy-skate-park-basics. It is just answer and questions. No paper writing


HS Student Handout Conservation Energy NGSS .docx Instruction to Laboratory Online Activity. Conservation of Energy at the Skate Park Name:___________ Learning Objective: To investigate the conservation of mechanical energy in a system. 1- Theoretical introduction. Use the text book, Chapter 7. Potential energy is the amount of energy that is stored within a system. Potential energy exists whenever an object has a position within a force field. The most familiar example of this is the position of objects in the Earth's gravitational field. The potential energy of an object in this case is given by the relation: PE = mgh, where: · PE = Energy (in Joules) · m = mass (in kilograms) · g = gravitational acceleration of the earth (9.8 m/sec2) · h = height above earth's surface (in meters) Kinetic Energy exists when an object is in motion. The kinetic energy of an object in this case is given by the relation: KE = (1/2)mv2 , where: · KE = Energy (in Joules) · m = mass (in kilograms) · v = velocity (in meters/sec) The following image illustrates a ball being thrown up in the air. When the ball is at its highest position above the ground it is at its maximum potential energy. Maximum Potential Energy, Minimum Kinetic Energy Maximum Kinetic Energy, Minimum Potential Energy Maximum Kinetic Energy, Minimum Potential Energy An object reaches its maximum kinetic energy when it reaches its highest velocity. In the example above, as the ball falls its potential energy decreases because its position relative to the ground is decreasing. The Conservation principle of Energy. The total amount of mechanical energy in an isolated system is conserved. This means that the amount of energy that an object has does not disappear when acted upon by outside forces, but instead transforms into another form of energy. ET =KE+PE =Constant. ET- the total amount of Mechanical energy. Meaning that in 2 different points of the system without the friction ET1=ET2 KE1 +PE1 = KE2+ PE2 The Conservation principle of Energy for two points of the system In the presence of external force (friction force), Need to considering one part of total energy will transform in Thermal Energy. 2. Work with Phet Simulation Energy Skate park. Watch the video: “ How to Use Skateboard Simulation” https://www.youtube.com/watch?v=IsQqAM0YMH0 Open the Colorado Phet “Skate Park Physics”. https://phet.colorado.edu/en/simulation/energy-skate-park-basics Exploration:(Click on “Intro”) 1. Place the skater somewhere on the ramp. Watch what happens to the skater. 1. Try moving the skater to different starting points on the ramp by clicking on the skater in the red box 1. Explore different ramps and observe how the skate moves. 1. Try different tools in the box in the top right. Lab questions. 1. Place the skater at the top of the half-pipe and press the > button to allow him to move. Make sure he starts from rest! a. Describe what happens to the skater: _________________________________________________________________ b. Turn on the Bar graph and Speed indicator and complete the energy chart below by pausing the motion at the different points indicated: Top Right of Ramp Bottom of Ramp Top Left of Ramp 2. Discuss the energy changes that you see in the bar charts. The bar chart shows the following energies: Energy of motion (Kinetic energy), Energy due to the skater’s height above ground (Gravitational potential energy) Total mechanical energy (Kinetic energy + Gravitational Potential Energy) Thermal Energy (Heat energy generated by friction) i. Which energy bar stayed constant ALL THE TIME: ______________________ ii. Which energy was at a maximum when the skater has a the top of the pipe:_______________ iii. Which energy was at a maximum when the skater was at the bottom of the pipe:___________ iv. Which energy always stayed at zero? ________________ (This makes sense because there Is no friction here! c. Turn on the speed dial. Discuss the skater’s speed at the top and bottom of the pipe. Speed at top of pipe:___________________________________________ Speed at bottom of pipe:___________________________________________ d. Explain how the speed is connected to the energy values in part c. _____________________ 3. Click on the Friction Icon at the Bottom of the screen. Run the simulation again with friction in the MIDDLE of the setting range: a) Complete the chart. Top Right of Ramp Bottom of Ramp Top Left of Ramp b. Discuss what happens to the skater over time in this case. ____________________________________________________________________________ ____________________________________________________________________________ C. Why does the skater eventually stop? ____________________________________________________________________________ ____________________________________________________________________________ Consolidation Questions: 1. Discuss what happens to the form of energy as the skater rolls down the hill. (Hint: discuss the conversion of energy). _______________________________________________________________________ _______________________________________________________________________ 2. If there is no friction in the system, what can we conclude about the total mechanical energy? ___________________________________________________________________ ___________________________________________________________________ 3. What kind of energy is generated when friction is present? ___________________________________________________________________ ___________________________________________________________________ 4. How does friction affect the mechanical energy in the system? ___________________________________________________________________ ___________________________________________________________________ Additional Questions.