Regents Physics Most Missed Questions of 2014 Review

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1 Regents Physics Most Missed Questions of 2014 Review Answers And Explanations Here: 1. A sound wave traveling eastward through air causes the air molecules to 1) vibrate east and west 2) vibrate north and south 3) move eastward, only 4) move northward, only 2. In the diagram below, a 20.-newton force due north and a 20.-newton force due east act concurrently on an object, as shown in the diagram below. 5. In the diagram below, 400. joules of work is done raising a 72-newton weight a vertical distance of 5.0 meters. The additional force necessary to bring the object into a state of equilibrium is 1) 20. N, northeast 2) 20. N, southwest 3) 28 N, northeast 4) 28 N, southwest 3. A 15.0-kilogram mass is moving at 7.50 meters per second on a horizontal, frictionless surface. What is the total work that must be done on the mass to increase its speed to 11.5 meters per second? 1) 120. J 2) 422 J 3) 570. J 4) 992 J 4. A circuit consists of a resistor and a battery. Increasing the voltage of the battery while keeping the temperature of the circuit constant would result in an increase in 1) current, only 2) resistance, only 3) both current and resistance 4) neither current nor resistance How much work is done to overcome friction as the weight is raised? 1) 40. J 2) 360 J 3) 400. J 4) 760 J 6. A tuning fork vibrating in air produces sound waves. These waves are best classified as 1) transverse, because the air molecules are vibrating parallel to the direction of wave motion 2) transverse, because the air molecules are vibrating perpendicular to the direction of wave motion 3) longitudinal, because the air molecules are vibrating parallel to the direction of wave motion 4) longitudinal, because the air molecules are vibrating perpendicular to the direction of wave motion 7. A 512-hertz sound wave travels 100. meters to an observer through air at STP. What is the wavelength of this sound wave? 1) m 2) m 3) 1.55 m 4) 5.12 m Page 1

2 8. Several pieces of copper wire, all having the same length but different diameters, are kept at room temperature. Which graph best represents the resistance, R, of the wires as a function of their cross-sectional areas, A? 9. According to the Standard Model, a proton is constructed of two up quarks and one down quark (uud) and a neutron is constructed of one up quark and two down quarks (udd). During beta decay, a neutron decays into a proton, an electron, and an electron antineutrino. During this process there is a conversion of a 1) u quark to a d quark 2) d quark to a meson 3) baryon to another baryon 4) lepton to another lepton 10. Which combination of fundamental units can be used to express energy? 1) kg m/s 2) kg m 2 /s 3) kg m/s 2 4) kg m 2 /s A block weighing 40. newtons is released from rest on an incline 8.0 meters above the horizontal, as shown in the diagram below. 13. The diagram below represents the magnetic field near point P. If a compass is placed at point P in the same plane as the magnetic field, which arrow represents the direction the north end of the compass needle will point? If 50. joules of heat is generated as the block slides down the incline, the maximum kinetic energy of the block at the bottom of the incline is 1) 50. J 2) 270 J 3) 320 J 4) 3100 J 12. A wave passes through an opening in a barrier. The amount of diffraction experienced by the wave depends on the size of the opening and the wave s 1) amplitude 2) wavelength 3) velocity 4) phase Page 2

3 14. A 3.0-kilogram steel block is at rest on a friction-less horizontal surface. A 1.0-kilogram lump of clay is propelled horizontally at 6.0 meters per second toward the block as shown in the diagram below. 19. The graph below shows the relationship between the speed and elapsed time for an object falling freely from rest near the surface of a planet. Upon collision, the clay and steel block stick together and move to the right with a speed of 1) 1.5 m/s 2) 2.0 m/s 3) 3.0 m/s 4) 6.0 m/s 15. Two 20.-newton forces act concurrently on an object. What angle between these forces will produce a resultant force with the greatest magnitude? 1) 0º 2) 45º 3) 90.º 4) 180.º 16. The speed of an object undergoing constant acceleration increases from 8.0 meters per second to 16.0 meters per second in 10. seconds. How far does the object travel during the 10. seconds? 1) m 2) m 3) m 4) m 17. The diagram below shows a force of magnitude F applied to a mass at angle relative to a horizontal frictionless surface. What is the total distance the object falls during the first 3.0 seconds? 1) 12 m 2) 24 m 3) 44 m 4) 72 m 20. A boat weighing Newtons requires a horizontal force of Newtons to move it across the water at meters per second. The boat s engine must provide energy at the rate of 1) J 2) W 3) J 4) W 21. A 5.0-newton force and a 7.0-newton force act concurrently on a point. As the angle between the forces is increased from 0 to 180, the magnitude of the resultant of the two forces changes from 1) 0.0 N to 12.0 N 2) 2.0 N to 12.0 N 3) 12.0 N to 2.0 N 4) 12.0 N to 0.0 N 22. The graph below represents the relationship between speed and time for an object moving along a straight line. As angle is increased, the horizontal acceleration of the mass 1) decreases 2) increases 3) remains the same 18. Which unit is equivalent to a newton per kilogram? 1) m s 2) W s 3) J s 4) kg m s What is the total distance traveled by the object during the first 4 seconds? 1) 5 m 2) 20 m 3) 40 m 4) 80 m Page 3

4 23. The diagram below represents a force vector, A and resultant vector, R. Which force vector B below could be added to force vector A to produce resultant vector, R. 24. Two forces act concurrently on an object. Their resultant force has the largest magnitude when the angle between the forces is 1) 0 2) 30 3) 90 4) The diagram below represents two masses before and after they collide. Before the collision, mass ma is moving to the right with speed v, and mass mb is at rest. Upon collision, the two masses stick together. Which expression represents the speed, v', of the masses after the collision? [Assume no outside forces are acting on ma or mb.] 26. A wooden crate is pushed at constant speed across a level wooden floor. Which graph best represents the relationship between the total mechanical energy of the crate and the duration of time the crate is pushed? Page 4

5 27. If the magnitude of the gravitational force of Earth on the Moon is F, the magnitude of the gravitational force of the Moon on Earth is 1) smaller than F 2) larger than F 3) equal to F 28. Two 30.-newton forces act concurrently on an object. In which diagram would the forces produce a resultant with a magnitude of 30. newtons? 1) 2) 30. A high school physics student is sitting in a seat reading this question. The magnitude of the force with which the seat is pushing up on the student to support him is closest to 1) 0 N 2) 60 N 3) 600 N 4) 6,000 N 31. A baseball player runs 27.4 meters from the batter's box to first base, overruns first base by 3.0 meters, and then returns to first base. Compared to the total distance traveled by the player, the magnitude of the player's total displacement from the batter's box is 1) 3.0 m shorter 2) 6.0 m shorter 3) 3.0 m longer 4) 6.0 m longer 32. The diagram below shows a moving, 5.00-kilogram cart at the foot of a hill 10.0 meters high. For the cart to reach the top of the hill, what is the minimum kinetic energy of the cart in the position shown? [Neglect energy loss due to friction.] 3) 4) 29. Base your answer to the following question on the information and table below. The weight of an object was determined at five different distances from the center of Earth. The results are shown in the table below. Position A represents results for the object at the surface of Earth. 1) 4.91 J 2) 50.0 J 3) 250. J 4) 491 J 33. A sonar wave is reflected from the ocean floor. For which angles of incidence do the wave s angle of reflection equal its angle of incidence? 1) angles less than 45, only 2) an angle of 45, only 3) angles greater than 45, only 4) all angles of incidence 34. Parallel wave fronts incident on an opening in a barrier are diffracted. For which combination of wavelength and size of opening will diffraction effects be greatest? 1) short wavelength and narrow opening 2) short wavelength and wide opening 3) long wavelength and narrow opening 4) long wavelength and wide opening 35. A car travels at constant speed v up a hill from point A to point B, as shown in the diagram below. As the car travels from A to B, its gravitational potential energy At what distance from the center of Earth is the weight of the object approximately 28 newtons? 1) m 2) m 3) m 4) m 1) increases and its kinetic energy decreases 2) increases and its kinetic energy remains the same 3) remains the same and its kinetic energy decreases 4) remains the same and its kinetic energy remains the same Page 5

6 36. As a box is pushed 30. meters across a horizontal floor by a constant horizontal force of 25 newtons, the kinetic energy of the box increases by 300. joules. How much total internal energy is produced during this process? 38. The graph below shows elongation as a function of the applied force for two springs, A and B. 1) 150 J 2) 250 J 3) 450 J 4) 750 J 37. A 1,200-kilogram car traveling at 10. meters per second hits a tree and is brought to rest in 0.10 second. What is the magnitude of the average force acting on the car to bring it to rest? 1) N 2) N 3) N 4) N Compared to the spring constant for spring A, the spring constant for spring B is 1) smaller 2) larger 3) the same 39. A car s horn produces a sound wave of constant frequency. As the car speeds up going away from a stationary spectator, the sound wave detected by the spectator 1) decreases in amplitude and decreases in frequency 2) decreases in amplitude and increases in frequency 3) increases in amplitude and decreases in frequency 4) increases in amplitude and increases in frequency 40. A plane flying horizontally above Earth s surface at 100. meters per second drops a crate. The crate strikes the ground 30.0 seconds later. What is the magnitude of the horizontal component of the crate s velocity just before it strikes the ground? [Neglect friction.] 1) 0 m/s 2) 100. m/s 3) 294 m/s 4) 394 m/s Page 6

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8 Answer Key Most Missed Questions 2014 Review Answers and explanations Here: Page 11