# Physical Setting 21 June 2007

Physical Setting 21 June 2007 Questions Answer Keys

The University of the State of New York
Regents High School Examination
Physical Setting
Physics
Thursday, June 21, 2007 — 9:15 a.m. to 12:15 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 not a vector quantity?

• (1) electric charge
• (2) magnetic field strength
• (3) velocity
• (4) displacement

2. An astronaut standing on a platform on the Moon drops a hammer. If the hammer falls 6.0 meters vertically in 2.7 seconds, what is its acceleration?

• (1) 1.6 m/s2
• (2) 2.2 m/s2
• (3) 4.4 m/s2
• (4) 9.8 m/s2

3. A 2.00-kilogram object weighs 19.6 newtons on Earth. If the acceleration due to gravity on Mars is 3.71 meters per second2, what is the object’s mass on Mars?

• (1) 2.64 kg
• (2) 2.00 kg
• (3) 19.6 N
• (4) 7.42 N

4. A car moves with a constant speed in a clockwise direction around a circular path of radius r, as represented in the diagram below.

When the car is in the position shown, its acceleration is directed toward the

• (1) north
• (2) west
• (3) south
• (4) east

Note that question 5 has only three choices.

5. As the angle between two concurrent forces decreases, the magnitude of the force required to produce equilibrium

• (1) decreases
• (2) increases
• (3) remains the same

6. A child walks 5.0 meters north, then 4.0 meters east, and finally 2.0 meters south. What is the magnitude of the resultant displacement of the child after the entire walk?

• (1) 1.0 m
• (2) 5.0 m
• (3) 3.0 m
• (4) 11.0 m

7. The diagram below represents a spring hanging vertically that stretches 0.075 meter when a 5.0- newton block is attached. The spring-block system is at rest in the position shown.

The value of the spring constant is

• (1) 38 N/m
• (2) 67 N/m
• (3) 130 N/m
• (4) 650 N/m

8. A 0.50-kilogram object moves in a horizontal circular path with a radius of 0.25 meter at a constant speed of 4.0 meters per second. What is the magnitude of the object’s acceleration?

• (1) 8.0 m/s2
• (2) 16 m/s2
• (3) 32 m/s2
• (4) 64 m/s2

9. Which situation will produce the greatest change of momentum for a 1.0-kilogram cart?

• (1) accelerating it from rest to 3.0 m/s
• (2) accelerating it from 2.0 m/s to 4.0 m/s
• (3) applying a net force of 5.0 N for 2.0 s
• (4) applying a net force of 10.0 N for 0.5 s

10. Earth’s mass is approximately 81 times the mass of the Moon. If Earth exerts a gravitational force of magnitude F on the Moon, the magnitude of the gravitational force of the Moon on Earth is

• (1) F
• (2) F/81
• (3) 9F
• (4) 81F

11. The table below lists the mass and speed of each of four objects.

Which two objects have the same kinetic energy?

• (1) A and D
• (2) B and D
• (3) A and C
• (4) B and C

12. A horizontal force of 5.0 newtons acts on a 3.0-kilogram mass over a distance of 6.0 meters along a horizontal, frictionless surface. What is the change in kinetic energy of the mass during its movement over the 6.0-meter distance?

• (1) 6.0 J
• (2) 15 J
• (3) 30. J
• (4) 90. J

13. Which quantity is a measure of the rate at which work is done?

• (1) energy
• (2) power
• (3) momentum
• (4) velocity

14. The diagram shows two bowling balls, A and B, each having a mass of 7.00 kilograms, placed 2.00 meters apart.

What is the magnitude of the gravitational force exerted by ball A on ball B?

• (1) 8.17 × 10–9 N
• (2) 1.63 × 10–9 N
• (3) 8.17 × 10–10 N
• (4) 1.17 × 10–10 N

15. If 1.0 joule of work is required to move 1.0 coulomb of charge between two points in an electric field, the potential difference between the two points is

• (1) 1.0 × 100 V
• (2) 9.0 × 109 V
• (3) 6.3 × 1018 V
• (4) 1.6 × 10–19 V

16. The current through a 10.-ohm resistor is 1.2 amperes. What is the potential difference across the resistor?

• (1) 8.3 V
• (2) 12 V
• (3) 14 V
• (4) 120 V

17. A copper wire of length L and cross-sectional area A has resistance R. A second copper wire at the same temperature has a length of 2L and a cross-sectional area of 1/2 A. What is the resistance of the second copper wire?

• (1) R
• (2) 2R
• (3) 1/2 R
• (4) 4R

18. A 6.0-ohm lamp requires 0.25 ampere of current to operate. In which circuit below would the lamp operate correctly when switch S is closed?

19. What is the total current in a circuit consisting of six operating 100-watt lamps connected in parallel to a 120-volt source?

• (1) 5 A
• (2) 20 A
• (3) 600 A
• (4) 12 000 A

20. A 4.50-volt personal stereo uses 1950 joules of electrical energy in one hour. What is the electrical resistance of the personal stereo?

• (1) 433 Ω
• (2) 96.3 Ω
• (3) 37.4 Ω
• (4) 0.623 Ω

21. As yellow light (f = 5.09 × 1014 Hz) travels from zircon into diamond, the speed of the light

• (1) decreases
• (2) increases
• (3) remains the same

22. The diagram below represents a transverse wave.

The distance between which two points identifies the amplitude of the wave?

• (1) A and B
• (2) A and C
• (3) A and E
• (4) D and E

23. The diagram below represents a periodic wave.

Which point on the wave is in phase with point P?

• (1) A
• (2) B
• (3) C
• (4) D

24. What is the period of a 60.-hertz electromagnetic wave traveling at 3.0 × 108 meters per second?

• (1) 1.7 × 10–2 s
• (2) 2.0 × 10–7 s
• (3) 6.0 × 101 s
• (4) 5.0 × 106 s

25. At an outdoor physics demonstration, a delay of 0.50 second was observed between the time sound waves left a loudspeaker and the time these sound waves reached a student through the air. If the air is at STP, how far was the student from the speaker?

• (1) 1.5 × 10–3 m
• (2) 1.7 × 102 m
• (3) 6.6 × 102 m
• (4) 1.5 × 108 m

26. A microwave and an x ray are traveling in a vacuum. Compared to the wavelength and period of the microwave, the x ray has a wavelength that is

• (1) longer and a period that is shorter
• (2) longer and a period that is longer
• (3) shorter and a period that is longer
• (4) shorter and a period that is shorter

27. Which type of wave requires a material medium through which to travel?

• (1) electromagnetic
• (2) infrared
• (3) sound

28. A car traveling at 70 kilometers per hour accelerates to pass a truck. When the car reaches a speed of 90 kilometers per hour the driver hears the glove compartment door start to vibrate. By the time the speed of the car is 100 kilometers per hour, the glove compartment door has stopped vibrating. This vibrating phenomenon is an example of

• (1) the Doppler effect
• (2) diffraction
• (3) resonance
• (4) destructive interference

29. A beam of monochromatic light approaches a barrier having four openings, A, B, C, and D, of different sizes as shown below.

Which opening will cause the greatest diffraction?

• (1) A
• (2) B
• (3) C
• (4) D

30. Two waves having the same frequency and amplitude are traveling in the same medium. Maximum constructive interference occurs at points where the phase difference between the two superposed waves is

• (1) 0°
• (2) 90°
• (3) 180°
• (4) 270°