CJC 2016 A level H2 Physics Answers

1    H2 Physics 9646 – 2016 A Level Exam Highlight in YELLOW the recommended qns to go through in Class Paper 1 1 No specific keywords in questions, but prefixes is the key in evaluating the answer. Answer: B 2 Keywords  Estimate (need not be exact, but choose the nearest answer)  Photon, Green light  Energy Essential Questions:  How do we calculate the energy of a photon?  What is an estimate of the wavelength of green light? Answer: C 3 Keywords  700 km/h airspeed  250 km/h from west  Resultant Directly North Essential Questions:  How should the aircraft fly towards so that the resultant velocity is directly north?  What is the vector diagram and what are the vectors to be drawn? (name the 3 vectors to be drawn: initial velocity of aircraft, change in velocity of caused by the wind, final/resultant velocity of the aircraft) Answer: B 4 Keywords  velocity-time graph  displacement-time graph  acceleration-time graph  velocity-distance graph Essential Questions:  How do we translate from velocity-time graph to other graphs?  What are the information from a velocity-time graph can we get from the features of such a graph? A possible method to solve this question is to evaluate each graph with the features from the given graph. For example, for a acceleration-time graph, there must be a horizontal line at 0. Answer: D 5 Keywords  Flat golf course  falls back to the original height  Horizontal distance  Maximum height  Angle  (thematic words indicating kinematics and projectile motion) Essential Questions  What are implicit info at the ‘max height’ and ‘when it returns to the original height’?  What kinematics equations are applicable?

2    Answer: D 6 Keywords:  Total momentum  After collision Essential Questions:  Is total momentum conserved? Is there any net external force on the system? Answer: C 7 Keywords:  Free to move without friction Essential Questions:  What is the relationship between force, speed and time?  Does the gradient and/or the area under a F-t graph represent anything useful?  What is the gradient of speed–time graph? Answer: D 8 Keywords:  Range of minimum forces Essential Questions:  What are the forces acted on the block when it is completely submerge?  What are the forces acted on the block when it is completely lifted out of water?  When does minimum force occur? (  lifted at constant velocity) Answer: D 9 Keywords:  Force from the slope on the skier Essential questions: 1. Draw the free body diagram of the skier 2. Draw the vector diagram of the forces in equilibrium Answer: B 10 Keywords:  Couple of torque M  Torque of couple Essential  How to determine the torque of a couple? Answer: C 11 Key info: - Constant speed - Level road - Efficiency is 16% - Travel 1 km - 1 kg of fuel provides 48 MJ of energy Essential questions:  How much energy is