# Physical Setting 24 January 2008

Physical Setting 24 January 2008 Questions Answer Keys

The University of the State of New York
Regents High School Examination
Physical Setting
Physics
Thursday, January 24, 2008 — 1:15 to 4:15 p.m., only

Directions (1–30): For each statement or question, write on the separate answer sheet the number of the word or expression that, of those given, best completes the statement or answers the question.

1. Which is a vector quantity?

• (1) speed
• (2) work
• (3) mass
• (4) displacement

2. A race car starting from rest accelerates uniformly at a rate of 4.90 meters per second2. What is the car’s speed after it has traveled 200. meters?

• (1) 1960 m/s
• (2) 62.6 m/s
• (3) 44.3 m/s
• (4) 31.3 m/s

3. A ball is thrown straight downward with a speed of 0.50 meter per second from a height of 4.0 meters. What is the speed of the ball 0.70 second after it is released? [Neglect friction.]

• (1) 0.50 m/s
• (2) 7.4 m/s
• (3) 9.8 m/s
• (4) 15 m/s

4. A soccer player kicks a ball with an initial velocity of 10. meters per second at an angle of 30.° above the horizontal. The magnitude of the horizontal component of the ball’s initial velocity is

• (1) 5.0 m/s
• (2) 8.7 m/s
• (3) 9.8 m/s
• (4) 10. m/s

5. Which object has the greatest inertia?

• (1) a 5.00-kg mass moving at 10.0 m/s
• (2) a 10.0-kg mass moving at 1.00 m/s
• (3) a 15.0-kg mass moving at 10.0 m/s
• (4) a 20.0-kg mass moving at 1.00 m/s

6. A 60.-kilogram physics student would weigh 1560 newtons on the surface of planet X. What is the magnitude of the acceleration due to gravity on the surface of planet X?

• (1) 0.038 m/s2
• (2) 6.1 m/s2
• (3) 9.8 m/s2
• (4) 26 m/s2

7. Two spheres, A and B, are simultaneously projected horizontally from the top of a tower. Sphere A has a horizontal speed of 40. meters per second and sphere B has a horizontal speed of 20. meters per second. Which statement best describes the time required for the spheres to reach the ground and the horizontal distance they travel? [Neglect friction and assume the ground is level.]

• (1) Both spheres hit the ground at the same time and at the same distance from the base of the tower.
• (2) Both spheres hit the ground at the same time, but sphere A lands twice as far as sphere B from the base of the tower.
• (3) Both spheres hit the ground at the same time, but sphere B lands twice as far as sphere A from the base of the tower.
• (4) Sphere A hits the ground before sphere B, and sphere A lands twice as far as sphere B from the base of the tower.

8. 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.

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

9. A car’s performance is tested on various horizontal road surfaces. The brakes are applied, causing the rubber tires of the car to slide along the road without rolling. The tires encounter the greatest force of friction to stop the car on

• (1) dry concrete
• (2) dry asphalt
• (3) wet concrete
• (4) wet asphalt

10. A car rounds a horizontal curve of constant radius at a constant speed. Which diagram best represents the directions of both the car’s velocity, v, and acceleration, a?

11. A 6.0-kilogram block, sliding to the east across a horizontal, frictionless surface with a momentum of 30. kilogram•meters per second, strikes an obstacle. The obstacle exerts an impulse of 10. newton•seconds to the west on the block. The speed of the block after the collision is

• (1) 1.7 m/s
• (2) 3.3 m/s
• (3) 5.0 m/s
• (4) 20. m/s

12. If a 65-kilogram astronaut exerts a force with a magnitude of 50. newtons on a satellite that she is repairing, the magnitude of the force that the satellite exerts on her is

• (1) 0 N
• (2) 50. N less than her weight
• (3) 50. N more than her weight
• (4) 50. N

13. A 1.0-kilogram laboratory cart moving with a velocity of 0.50 meter per second due east collides with and sticks to a similar cart initially at rest. After the collision, the two carts move off together with a velocity of 0.25 meter per second due east. The total momentum of this frictionless system is

• (1) zero before the collision
• (2) zero after the collision
• (3) the same before and after the collision
• (4) greater before the collision than after the collision

14. Student A lifts a 50.-newton box from the floor to a height of 0.40 meter in 2.0 seconds. Student B lifts a 40.-newton box from the floor to a height of 0.50 meter in 1.0 second. Compared to student A, student B does

• (1) the same work but develops more power
• (2) the same work but develops less power
• (3) more work but develops less power
• (4) less work but develops more power

15. While riding a chairlift, a 55-kilogram skier is raised a vertical distance of 370 meters. What is the total change in the skier’s gravitational potential energy?

• (1) 5.4 × 101 J
• (2) 5.4 × 102 J
• (3) 2.0 × 104 J
• (4) 2.0 × 105 J

16. The work done on a slingshot is 40.0 joules to pull back a 0.10-kilogram stone. If the slingshot projects the stone straight up in the air, what is the maximum height to which the stone will rise? [Neglect friction.]

• (1) 0.41 m
• (2) 41 m
• (3) 410 m
• (4) 4.1 m

17. A 0.686-meter-long wire has a cross-sectional area of 8.23 × 10–6 meter2 and a resistance of 0.125 ohm at 20° Celsius. This wire could be made of

• (1) aluminum
• (2) copper
• (3) nichrome
• (4) tungsten

18. A block weighing 40. newtons is released from rest on an incline 8.0 meters above the horizontal, as shown in the diagram below.

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

19. The diagram below represents an electron within an electric field between two parallel plates that are charged with a potential difference of 40.0 volts.

If the magnitude of the electric force on the electron is 2.00 × 10–15 Newton, the magnitude of the electric field strength between the charged plates is

• (1) 3.20 × 10–34 N/C
• (2) 2.00 × 10–14 N/C
• (3) 1.25 × 104 N/C
• (4) 2.00 × 1016 N/C

20. A circuit consists of a 10.0-ohm resistor, a 15.0-ohm resistor, and a 20.0-ohm resistor connected in parallel across a 9.00-volt battery. What is the equivalent resistance of this circuit?

• (1) 0.200 Ω
• (2) 1.95 Ω
• (3) 4.62 Ω
• (4) 45.0 Ω

21. An electric circuit contains a variable resistor connected to a source of constant potential difference. Which graph best represents the relationship between current and resistance in this circuit?

22. In the circuit diagram below, two 4.0-ohm resistors are connected to a 16-volt battery as shown.

The rate at which electrical energy is expended in this circuit is

• (1) 8.0 W
• (2) 16 W
• (3) 32 W
• (4) 64 W

23. Increasing the amplitude of a sound wave produces a sound with

• (1) lower speed
• (2) higher pitch
• (3) shorter wavelength
• (4) greater loudness

24. The product of a wave’s frequency and its period is

• (1) one
• (2) its velocity
• (3) its wavelength
• (4) Planck’s constant

25. A periodic wave having a frequency of 5.0 hertz and a speed of 10. meters per second has a wavelength of

• (1) 0.50 m
• (2) 2.0 m
• (3) 5.0 m
• (4) 50. m

26. An electromagnetic wave traveling through a vacuum has a wavelength of 1.5 × 10–1 meter. What is the period of this electromagnetic wave?

• (1) 5.0 × 10–10 s
• (2) 1.5 × 10–1 s
• (3) 4.5 × 107 s
• (4) 2.0 × 109 s

27. A ray of light (f = 5.09 × 1014 Hz) traveling in air strikes a block of sodium chloride at an angle of incidence of 30.°. What is the angle of refraction for the light ray in the sodium chloride?

• (1) 19°
• (2) 25°
• (3) 40.°
• (4) 49°

28. The speed of a ray of light traveling through a substance having an absolute index of refraction of 1.1 is

• (1) 1.1 × 108 m/s
• (2) 2.7 × 108 m/s
• (3) 3.0 × 108 m/s
• (4) 3.3 × 108 m/s

29. Resonance occurs when one vibrating object transfers energy to a second object causing it to vibrate. The energy transfer is most efficient when, compared to the first object, the second object has the same natural

• (1) frequency
• (2) loudness
• (3) amplitude
• (4) speed

30. A subatomic particle could have a charge of

• (1) 5.0 × 10–20 C
• (2) 8.0 × 10–20 C
• (3) 3.2 × 10–19 C
• (4) 5.0 × 10–19 C