Free Response Question#1 : Some of these components of this question were marked wrong or marked half-wrong (questions wrong, or not fully correct, are circled in blue ink) on a test. I need the correct answers and explanations for test corrections.

( Green color ink - Teacher's grading and comments)

me_ Hadley Fralin Period 4 4 AP PHYSICS-1 (2021-2022) Date 2- 9- 22 Time Limit: 40 Minutes TEST 4: Energy- FREE RESPONSE Calculator Formula & Sheet NOT Allowed On my honor, I have neither given nor received any aid on this exam. fladay fualin 1. time 20 minutes) This question is a long free-response question. Show your work for each part of the question. (15 points, suggested 62-5 PET 11250 P= work izl KEV 125 OS K= 2 muz FN D TYPE = KE i PE = KE 10 m PE=Ugh ( Inputted ) PET KET1 Iramp F =M. a -x--1 PEN Work = FX Ax leads to PE smis ( imputted ) F= = H. N A box is pressed against a horizontal spring, compressing the spring from its relaxed length. The box is then KE released, and the spring launches the box horizontally along a track that ends in a ramp, as shown above. The box has enough speed to leave the ramp, and the box reaches a maximum vertical height above the floor. Assume there s negligible friction between the box and the track and air resistance is negligible. k is the spring stiffness constant KE = /2 (5 ) (5 ) 2 1 / 12 ) (5 ) 2 PE = 5 ( 10) (10) PE= 2(10)(10) X is the distance the spring is compressed s ( 100) = 200 M is the mass of the box 12 ( 5) ( 25 ) 1/2 50 12125 0 is the angle of the incline PE = SOO -62.5 = 25 h is the maximum height reached by the box M is increasing so the spring provides asmaller acceleration, by each box so the box does not aqil que as fast The scenario is repeated using a different box with a greater mass. The spring is compressed the same distance X. (a) Indicate how h in this second scenario compares to h in the original scenario, and explain why without mathematically deriving a relation for h. PET with more mass - since the blockhas a greater mass than the prior block, KET with more mass the height the block is going to gain,due to will be shorter than the the height reached the prior block. This is because there is a greater (b) Students derive an equation for h in the original scenario, h = (sin?) : gravitational force on the 2Mg , which may or may not be correct. Is block ? 0/ 2 this equation consistent with your claim in part (a)? Explain why or why not. P= work K= = 1/muz ( sin ?0 ) Kx 2 PE = wgh ZMg Scantron M-882-E-5:41 work = Fxly Two students are discussing the work done on the system consisting of only the box between the instant just before the spring begins accelerating the box and the instant the box reaches the end of the ramp. The students make the following statements. KEXPE Student 1: At first, the mechanical energy of the system increases because the spring does positive work on the system. Then, the mechanical energy of the system increases again as the box travels up the ramp because the box's potential energy increases.strech the A box alone has no potential energy and energy it gains has to be J'explained through work. W= F - Ax ME;= MEF Student 2: The mechanical energy of the system remains constant while the spring pushes the box because the work done on the box by the spring cancels the work done by the spring on the box. Then, when the block is onthe ramp, the mechanical energy of the system decreases because the box slows down. velocity (c) Which underlined phrase or phrases in student I's statement are correct, if either? If neither phrase is correct, write "none . " 1- The second underlined phrase is correct because as the block goes higher UP, its Potential energy increase since save height is greater / the weight being the only thing that changes . within the (d) Which underlined phrase or phrases in student 1's statement are incorrect, if either? If neither phrase is + sys. Hmm- Encorrect, write "none." 9 - The first underlined phrase is correct (or somewhat ) because the imechanical energy is all potential, since the switched spring i's steving Up energy to release. The forces also cancel out write "none." (e) Which underlined phrase or phrases in student 2's statement are correct, if either? If neither phrase is correct, v - The first underlined phrase is incorrect because there is no work being done while the spring is pushed back, The fore needs to have ly in order f) Which underlined phrase or phrases in student 2's statement are incorrect, if either? If neither phrase is to have work . incorrect, write "none." - The second underlined phrase is in correct because as the block goes further or the ramp, the PE increases . (g) Does the mechanical energy of the box-spring-Earth system increase, decrease, or remain the same from the moment the spring is released until just before the box hits the ground? Justify your answer. 32 - Overall, the ME is constantly around the same since as KE goes up, PE goes down, while also answer (h) If air resistance were not negligible, how would that affect your answer to part (g), if at all? Justify your equal Someatives Vertical Velocity O Time (i) The graph above shows the vertical component of the velocity of the box as a function of time. The graph represents the entire time the box is in the air when the box is launched from the ramp at an angle 0 to the J horizontal. How would the total area under the curve be different, if at all, if the ramp angle O were increased but still less than 90 degrees, without changing the height of the end of the ramp? - The total area would be the same since the change in the angle will not effect the velocity 7 displacement but it does vertical velocity. affect the 8 "-TUUUT