Conservation of Energy and Work Energy Theorem . Objective The aim of the following laboratory simulation is to study the conservation of energy by letting a given mass fall down a ramp at different conditions. The second objective is to study the effects of friction and the Work energy theorem in a more realistic scenario. . Materials and Procedure In order to start working and performing the simulations, go to: https://phet.colorado.edu/en/simulation/legacy/energy-skate-park (You might need to download a java installation pack), it is safe! - Make sure you choose the second option - MEASURE simulation Follow the instructions given and make sure you ask questions as we go over the simulation - The main parts you should focus are: The mass and positions of the skater, the romp with and without friction and the ENERGY VS TIME GRAPH - Also, make sure you click on "CLEAR HEAT" in orderto ignore thermal energy release and focus on mechanical parameters ONLY. (If there is no option for this, do not worry about it)Part a) "Conservation of energy" In orderto study the conservation of energy, we will need first to write down the mass of the given skater: Build a track with an initial height of 8 meters, place the second "red dot" on the ground and the last one at a height of 4 meters. (Do not worry if the skater leaves the track after the simulation), make sure you pause so you can measure all the energies needed. M = Then, we will build a table of the form: Initial height (m) KEFT PERT 8.0 And a second table: Mechanical Energy initial (J) Mechanical Energy final (J) % error 1. Place the skater as shown in the picture below:Make sure you have activated both: The grid and the reference height. 2. The skater will be moving up and down and at some point might disappear. MAKE SURE YOU PAUSE THE SIMULATION BY CLICKING ON PAUSE. 3. Place the skater at a height of 8 meters and let it go. The skater will go down and then up and will leave the track. Make sure you try these enough times, so you get use to the simulation. 4. Use the measuring tool to find the values of energy at the beginning and right after the skater leaves the tracks. 5 Inthesecond table below the first one writes down the SUM of the initialand potential energies to get the TOTAL energy INITIALand FINAL 6. Perform an error calculation and discuss possible sources of error. Part b) "Work- Energy Theorem" To investigate the WORK - ENERGY theorem, we will add up friction into the mix. To do this, we will click on "TRACK FRICTION" and you will add friction to a certain degree. This will vary depending on each student. Just make sure you do not add too much that will affect the simulation itself. Just like before, write down the mass of the skater and build the following table: Mass of skater = Initial height (m) initial Final Friction 6.0 *Important. For this experiment you will use a semi - straight section of the ramp so you can easily pause the simulation. You will perform the simulation in slow mode and will measure the length of the ramp to compute the frictional force. 1. Release the skater from the top of the ramp again, this time however there is FRICTION. 2. Just like before, write down the KINETIC ENERGY when the skater reaches the bottom of the ramp and compute the initial POTENTIAL ENERGY by using the mass and height of the ramp.3. The idea now, is to compute the difference between the final and initial mechanical energies. Remember, the mechanical energy is the addition of both, potential and kinetic energies. 4. Repeat the experiment for additional three different heights. * Refer to the picture below to perform your own simulation. B O Ple Chart Speed Speed Stick to Track 8.8 m/s VLWb Height = 6.08 m Speed = 0.77 mis Friction Energy None Kinetic 17.7 J Potential 3573.3 J Gravity 9.8 m/s Thermal 2.2J OLI 260 Total 3593.3 J Earth Mass 60 kg Oi 0 m Height = 0 Grid Normal Restart Skater Reference Height ... Slow Computing the frictional force - To do this, SELECT one data point where you have the Work done by the friction.- Now, estimate the length of the ramp by "assuming" is perfectly straight. We know this is not the case, but use the height and using the grid, approximate the horizontal length and use the Py- thagorean Theorem to compute the length of the ramp. - Use this distance and the value of the work to compute an approximate value of the force. Questions to answer about this lab. 1. How good do you think were the values and approximations made in this lab? This includes your calculation of potential energy, your measurement of kinetic energy and the % error. 2. What changes will you make to this lab to increase its precision? 3. If you were doing this lab in a laboratory setting on campus, there will be friction for both of those cases, conservation, and work energy theorem. How will this affect your results? 4. How accurate do you thinkwas to compute the frictional force with the given procedure