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The melting point of aluminum is 660°C, its latent heat of fusion is 4.00 × 105 J/kg, and itsspecific heat is 900J/kg ∙ K. How much heat must be added to 500 g of aluminum originally at27°C to completely melt it? A) 485 kJ B) 395 kJ C) 273 kJ D) 147 kJ E) 14 kJ

A) 485 kJ

It is necessary to determine the specific heat of an unknown object. The mass of the object is 201g It is determined experimentally that it takes to 15J raise the temperature 10.0C What is the specific heat of the object? A) 7.46 J/kg ∙ K B) 1500 J/kg ∙ K C) 0.00130 J/kg ∙ K D) 3,020,000 J/kg ∙ K

A) 7.46 J/kg ∙ K

Four waves are described by the following equations, where distances are measured in meters and times in seconds. I. y = 0.12 cos(3x - 21t) II. y = 0.15 sin(6x + 42t) III. y = 0.13 cos(6x + 21t) IV. y = -0.23 sin(3x - 42t) Which of these waves have the same speed? A) I and II B) I and III C) II and III D) III and IV

A) I and II

If a wave has a speed of 362 m/s and a period of 4.17x10-3 s, what is its wavelength? A) 1510 m B) 1.51 m C) 86.8 m D) 86,800 m E) 0.0115 m

B) 1.51 m

A mass on a spring undergoes SHM. When the mass is at its maximum distance from the equilibrium position, which of the following statements about it are true? A) Its acceleration is zero. B) Its speed is zero. C) Its elastic potential energy is zero. D) Its kinetic energy is a maximum. E) Its total mechanical energy is zero.

B) Its speed is zero.

wo simple pendulums, A and B, are each 3.0 m long, and the period of pendulum A is T. Pendulum A is twice as heavy as pendulum B. What is the period of pendulum B? A) T/sqrt(2) B) T C) T*sqrt(2) D) 2T E) T/2

B) T

The process in which heat flows by the mass movement of molecules from one place toanother is known as A) conduction. B) convection. C) radiation.

B) convection.

The second law of thermodynamics leads us to conclude that A) the total energy of the universe is constant. B) disorder in the universe is increasing with the passage of time. C) it is theoretically possible to convert heat into work with 100% efficiency. D) the average temperature of the universe is increasing with the passage of time. E) the entropy of the universe remains constant.

B) disorder in the universe is increasing with the passage of time.

If you wanted to know how much the temperature of a particular piece of material would rise when a known amount of heat was added to it, which of the following quantities would be most helpful to know? A) initial temperature B) specific heat C) density D) coefficient of linear expansion E) thermal conductivity

B) specific heat

When you blow some air above a paper strip, the paper rises. This happens because A) the air above the paper moves faster and the pressure is higher. B) the air above the paper moves faster and the pressure is lower. C) the air above the paper moves faster and the pressure remains constant. D) the air above the paper moves slower and the pressure is higher. E) the air above the paper moves slower and the pressure is lower.

B) the air above the paper moves faster and the pressure is lower

You drop a stone down a well that is 9.5 m deep. How long is it before you hear the splash?The speed of sound in air is 343 m/s and air resistance is negligible. A) 1.2 s B) 1.3 s C) 1.4 s D) 1.5 s

C) 1.4 s

Water flows out of a large reservoir through an open pipe, as shown in the figure. What is the speed of the water as it comes out of the pipe? A) 8.9 m/s B) 9.9 m/s C) 13 m/s D) 14 m/s E) 16 m/s

C) 13 m/s

A 0.250-kg stone is attached to an ideal spring and undergoes simple harmonic oscillationswith a period of 0.640 s. What is the force constant (spring constant) of the spring? A) 2.45 N/m B) 12.1 N/m C) 24.1 N/m D) 0.102 N/m E) 0.610 N/m

C) 24.1 N/m

A gas is taken through the cycle shown in the pV diagram in the figure. During one cycle, how much work is done by the gas? A) p0V0 B) 2 p0V0 C) 3 p0V0 D) 4 p0V0

C) 3 p0V0

An ideal incompressible fluid flows at 16 m/s in a horizontal pipe. If the pipe widens to twiceits original radius, what is the flow speed in the wider section? A) 12 m/s B) 6.0 m/s C) 4.0 m/s D) 3.0 m/s

C) 4.0 m/s

A music tuner uses a 554-Hz C# tuning fork to tune the frequency of a musical instrument.If the tuner hears a beat frequency of 2 Hz, what is the frequency of the instrument? A) It must be 556 Hz. B) It must be 552 Hz. C) It could be either 556 Hz or 552 Hz. D) It could be either 553 Hz or 555 Hz. E) It is neither 556 Hz or 552 Hz

C) It could be either 556 Hz or 552 Hz.

A pendulum of length L is suspended from the ceiling of an elevator. When the elevator is at rest the period of the pendulum is T. How does the period of the pendulum change when the elevator moves upward with constant acceleration? A) The period does not change. B) The period increases. C) The period decreases. D) The period becomes zero. E) The period increases if the upward acceleration is more than g/2 but decreases if the upward acceleration is less than g/2.

C) The period decreases.

By what primary heat transfer mechanism does the sun warm the earth? A) convection B) conduction C) radiation D) All of the above processes are equally important in combination.

C) radiation

In simple harmonic motion, when is the speed the greatest? A) when the magnitude of the acceleration is a maximum B) when the displacement is a maximum C) when the potential energy is a maximum D) when the potential energy is a zero

D) when the potential energy is a zero

If your heart is beating at 76.0 beats per minute, what is the frequency of your heart'soscillations in hertz? A) 4560 Hz B) 1450 Hz C) 3.98 Hz D) 2.54 Hz E) 1.27 Hz

E) 1.27 Hz