# Physical Setting 26 January 2006

Physical Setting 26 January 2006 Questions Answer Keys

The University of the State of New York
Regents High School Examination
Physical Setting
Physics
Thursday, January 26, 2006 — 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. The speed of a wagon increases from 2.5 meters per second to 9.0 meters per second in 3.0 seconds as it accelerates uniformly down a hill. What is the magnitude of the acceleration of the wagon during this 3.0-second interval?

• (1) 0.83 m/s2
• (2) 2.2 m/s2
• (3) 3.0 m/s2
• (4) 3.8 m/s2

2. A 1.0-kilogram ball is dropped from the roof of a building 40. meters tall. What is the approximate time of fall? [Neglect air resistance.]

• (1) 2.9 s
• (2) 2.0 s
• (3) 4.1 s
• (4) 8.2 s

3. Which is a scalar quantity?

• (1) acceleration
• (2) momentum
• (3) speed
• (4) displacement

4. A projectile is fired with an initial velocity of 120. meters per second at an angle, , above the horizontal. If the projectile’s initial horizontal speed is 55 meters per second, then angle  measures approximately

• (1) 13°
• (2) 27°
• (3) 63°
• (4) 75°

5. A 2.0-kilogram laboratory cart is sliding across a horizontal frictionless surface at a constant velocity of 4.0 meters per second east. What will be the cart’s velocity after a 6.0-newton westward force acts on it for 2.0 seconds?

• (1) 2.0 m/s east
• (2) 2.0 m/s west
• (3) 10. m/s east
• (4) 10. m/s west

6. A 25.0-kilogram space probe fell freely with an acceleration of 2.00 meters per second2 just before it landed on a distant planet. What is the weight of the space probe on that planet?

• (1) 12.5 N
• (2) 25.0 N
• (3) 50.0 N
• (4) 250. N

Base your answers to questions 7 and 8 on the diagram below, which shows a 1.0-newton metal disk resting on an index card that is balanced on top of a glass.

7. What is the net force acting on the disk?

• (1) 1.0 N
• (2) 2.0 N
• (3) 0 N
• (4) 9.8 N

8. When the index card is quickly pulled away from the glass in a horizontal direction, the disk falls straight down into the glass. This action is a result of the disk’s

• (1) inertia
• (2) charge
• (3) shape
• (4) temperature

9. A vertical spring 0.100 meter long is elongated to a length of 0.119 meter when a 1.00-kilogram mass is attached to the bottom of the spring. The spring constant of this spring is

• (1) 9.8 N/m
• (2) 82 N/m
• (3) 98 N/m
• (4) 520 N/m

Note that question 10 has only three choices.

10. Compared to the force needed to start sliding a crate across a rough level floor, the force needed to keep it sliding once it is moving is

• (1) less
• (2) greater
• (3) the same

11. A 400-newton girl standing on a dock exerts a force of 100 newtons on a 10 000-newton sailboat as she pushes it away from the dock. How much force does the sailboat exert on the girl?

• (1) 25 N
• (2) 100 N
• (3) 400 N
• (4) 10 000 N

Note that question 12 has only three choices.

12. A student on her way to school walks four blocks east, three blocks north, and another four blocks east, as shown in the diagram.

Compared to the distance she walks, the magnitude of her displacement from home to school is

• (1) less
• (2) greater
• (3) the same

13. The diagram below represents two satellites of equal mass, A and B, in circular orbits around a planet.

Compared to the magnitude of the gravitational force of attraction between satellite A and the planet, the magnitude of the gravitational force of attraction between satellite B and the planet is

• (1) half as great
• (2) twice as great
• (3) one-fourth as great
• (4) four times as great

14. The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of 0.70-meter radius at a constant speed of 2.0 meters per second.

The magnitude of the centripetal force on the bucket of water is approximately

• (1) 5.7 N
• (2) 14 N
• (3) 29 N
• (4) 200 N

15. A 6.8-kilogram block is sliding down a horizontal, frictionless surface at a constant speed of 6.0 meters per second. The kinetic energy of the block is approximately

• (1) 20. J
• (2) 41 J
• (3) 120 J
• (4) 240 J

16. Through what vertical distance is a 50.-newton object moved if 250 joules of work is done against the gravitational field of Earth?

• (1) 2.5 m
• (2) 5.0 m
• (3) 9.8 m
• (4) 25 m

17. When a mass is placed on a spring with a spring constant of 15 newtons per meter, the spring is compressed 0.25 meter. How much elastic potential energy is stored in the spring

• (1) 0.47 J
• (2) 0.94 J
• (3) 1.9 J
• (4) 3.8 J

Note that question 18 has only three choices.

18. Two students of equal weight go from the first floor to the second floor. The first student uses an elevator and the second student walks up a flight of stairs. Compared to the gravitational potential energy gained by the first student, the gravitational potential energy gained by the second student is

• (1) less
• (2) greater
• (3) the same

19. A 55.0-kilogram diver falls freely from a diving platform that is 3.00 meters above the surface of the water in a pool. When she is 1.00 meter above the water, what are her gravitational potential energy and kinetic energy with respect to the water’s surface?

• (1) PE = 1620 J and KE = 0 J
• (2) PE = 1080 J and KE = 540 J
• (3) PE = 810 J and KE = 810 J
• (4) PE = 540 J and KE = 1080 J

20. A 0.25-kilogram baseball is thrown upward with a speed of 30. meters per second. Neglecting friction, the maximum height reached by the baseball is approximately

• (1) 15 m
• (2) 46 m
• (3) 74 m
• (4) 92 m

21. A truck weighing 3.0 × 104 newtons was driven up a hill that is 1.6 × 103 meters long to a level area that is 8.0 × 102 meters above the starting point. If the trip took 480 seconds, what was the minimum power required?

• (1) 5.0 × 104 W
• (2) 1.0 × 105 W
• (3) 1.2 × 1010 W
• (4) 2.3 × 1010 W

22. The graph below represents the relationship between the potential difference (V) across a resistor and the current (I) through the resistor.

Through which entire interval does the resistor obey Ohm’s law?

• (1) AB
• (2) BC
• (3) CD

23. Aluminum, copper, gold, and nichrome wires of equal lengths of 1.0 × 10–1 meter and equal cross-sectional areas of 2.5 × 10–6 meter2 are at 20.°C. Which wire has the greatest electrical resistance?

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

24. How much electrical energy is required to move a 4.00-microcoulomb charge through a potential difference of 36.0 volts?

• (1) 9.00 × 106 J
• (2) 144 J
• (3) 1.44 × 10–4 J
• (4) 1.11 × 10–7 J

25. What must be inserted between points A and B to establish a steady electric current in the incomplete circuit represented in the diagram below?

• (1) switch
• (2) voltmeter
• (3) magnetic field source
• (4) source of potential difference

26. In a series circuit containing two lamps, the battery supplies a potential difference of 1.5 volts. If the current in the circuit is 0.10 ampere, at what rate does the circuit use energy?

• (1) 0.015 W
• (2) 0.15 W
• (3) 1.5 W
• (4) 15 W

27. An electron placed between oppositely charged parallel plates A and B moves toward plate A, as represented in the diagram below.

What is the direction of the electric field between the plates?

• (1) toward plate A
• (2) toward plate B
• (3) into the page
• (4) out of the page

28. 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

29. How are electromagnetic waves that are produced by oscillating charges and sound waves that are produced by oscillating tuning forks similar?

• (1) Both have the same frequency as their respective sources.
• (2) Both require a matter medium for propagation.
• (3) Both are longitudinal waves.
• (4) Both are transverse waves.

30. The diagram below represents a transverse wave traveling in a string.

Which two labeled points are 180° out of phase?

• (1) A and D
• (2) B and F
• (3) D and F
• (4) D and H