USE:https://www.geogebra.org/m/ht8d7zfvREST IN PIC BELLOWNecessary Equipment:1. A Simulated Standard Ballistic Pendulum Apparatus & Ball (e.g., Geogebra) 2. A Simulated Standard Photogate & Digital Timer (e.g., Geogebra)3. A Simulated Medium-Size Paper & Wax-Coated CupUltimate Objectives:1. To apply the principles underlying projectile motion so as to make a verifiableretrodiction.2. To probe the connection between Galileo's Principle of Relativity (esp. "Form 4") and the principles underlying projectile motion.3. To use the laws of physics in a vivid forensic investigation.4. To not get hurt, by the awesomeness of this simulation.Immediate Objectives:1. To determine where a "weapon" (ballistic pendulum) must have been located if a "bullet"(brass sphere) hit a particular target.Specifically, to use analysis and computations (rather than trial and error) to determine where you must place your ballistic pendulum so that it successfully fires a brass sphere into a cup.2. To not get hurt, by the awesomeness of your retrodictive powers.What is known:1. ? ? ??/?2. Under constant acceleration, ?? = 1/2 ??^2 + ?t.3. Axes are independent: movement in the y direction does not affect movement in the x direction (from Galileo's Principle of Relativity).4. Gravity exerts a constant acceleration on all objects in free-fall, regardless of their initial velocity (discovered in lab 2).5. This constant acceleration, abbreviated g, is approximately 9.8 m/s2 (canonical).What is not known: Everything else.Procedures:I. The SimulationPart I- The Determining A. Unlike the real world this simulation can be put into full screen and be reverted back to its original configuration.B. Thesymbolonthebottomright-handsidecanbeusedtodisplaythesimulationinfull screen.C. Thesymbolonthetopright-handsidecanbeusedtorevertthesimulationtoits original configuration. This can be helpful if you happen to skew the view making it hard/impossible to continue the experiment.II. The Ballistic Pendulum.A. Observe your ballistic pendulum. Yours is one model of a classic piece of equipment--ultimately intended as a means for determining the speed of a fired bullet. We will return to its classic use later on in the course--during our investigation of energy and linear momentum conservation. Right now, we are using it as, simply put, a gun. More specifically, we are using the ballistic pendulum as a means for ensuring a reproducible and purely horizontal initial velocity.As you can see, this device has the potential to do real simulated damage--both to simulated inanimate and to simulated animate objects. We ask you to be cautious and responsible when using this simulation.III. The Photogate.A. The photogate, when connected to an appropriate output, provides the means for obtaining high-precision timings.The photogate uses an infrared beam that is part of an electrical circuit. When you press the manual switch, a timer begins counting. When the beam is broken by a passing object, the circuit is broken and the time is recorded.The virtual Photogate simulates the real version. If the ball Does Not go through the photogate, then No Time will be displayed.B. Youcanmovethephotogatesaroundbyclickingandholdingthemandmovingthem around the screen. Once the ball has been fired they will lock in place. Press Return to return the ball and unlock the photogates. REST IN PIC BELLOWA

gate -- shortly after it emerges from the firing mechanism. . O Tt 0 10 > C. The number that appears next to the photogate is the position of the photogate. IV. The Horizontal Component. E. Record the times and determine the horizontal velocity. A. Once you are familiar with the moving of the photogates, you will use it to obtain the horizontal velocity imparted by the firing mechanism to the brass sphere. F. Once you have determined your horizontal velocity you can uncheck Photogate Our working assumption is that the pendulum imparts a fairly reproducible velocity. V. The Vertical Component. B. Check the box labeled Photogate A. Using markings on the simulation, measure the height from which your sphere will be fired from the ballistic pendulum: in other words, measure the vertical displacement A net will appear. This net is to ensure the integrity of one of the purposes of the lab: that the bullet will have in the course of its trip. Use the variable y for vertical To determine where a "weapon" must have been to hit a target. The net will catch the displacement. y = ball, assuring that a "guess and check" approach is not used to determine the initial position of the "weapon" B. Determine how much time [sec] an object dropped from rest would take to free-fall the vertical displacement you obtained above. C. The photogate itself will produce a TIME. In order to determine a velocity, you will, of course, need a displacement. VI. Synthesis. Consider what displacement you need to measure in order to determine velocity. Consider why. A. If you think about it hard enough, you will see that you now have all the information you need in order to make a retrodiction. Hint: For a variety of reasons, particularly GPR, you can assume that the horizontal velocity of the brass sphere is essentially a constant: The initial, average and B. Assume that the weapon had been at the height you measured. Do whatever instantaneous at any point are all essentially the same. calculations you need to determine: Once you have decided what displacement to measure, answer the following at what Chorizontal) range from the target was the weapon? questions as preparation for your formal report: C. Once you have a horizontal range, you are to submit the Horizontal range & Work In 1 - 3 complete sentences of English, explain what you done to determine it to google classroom. measured for a displacement and why this measurement is D. Once submitted, the professor will review it relevant for a calculation of the sphere's velocity through the photogate. *** Let x stand for Horizontal Displacement. In meters, enter your displacement: x = m. D. Arrange your pendulum and photogate so that you can time the sphere through the gate -- shortly after it emerges from the firing mechanism