The curve represents an object in simple harmonic motion. Match the points on the curve to the velocity and acceleration of the object.

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1 On Friday, I will ask you to vote on the priority with which you want me to solve these problems. I will solve the most requested problem first and move to the least requested one. Please attempt all problems before coming to class. That way we will derive the most benefits from this review session. The curve represents an object in simple harmonic motion. Match the points on the curve to the velocity and acceleration of the object. 1. The velocity is positive, and the acceleration is zero. 2. The velocity is negative, and the acceleration is positive. 3. The velocity is positive, and the acceleration is negative. 4. The velocity is positive, and the acceleration is positive. 5. Shock absorbers are put on a car to damp out the oscillations that would occur when the springs are compressed. A car with no shocks has a spring on each wheel with k = 4500 N/m. It weighs 1000 kg, and holds 4 passengers, each with a mass of 70 kg. What would be the period of oscillation of the car (in sec) if it were to hit a rock or pot hole? A B C D E F G H

2 6. A stationary whistle emits a sound of 182 Hz. If a car hears the whistle with a frequency of 200 Hz, how fast was it moving (in m/s)? Use 340 m/s for the sound velocity. A B C D E F G H A gas is taken through the cyclic process described by the Figure above. How much work was done by the gas during the cycle ABCA? (in J) A 8317 B 9398 C D E F G H The motion of an object is described by the equation: x = (2.5 m) cos(πt/3.1), where t is assumed to be measured in seconds. What is the frequency (in Hz) of the motion? A B C D E F G H A piano emits sound waves with frequencies that range from a low of about 28 Hz to a high of about 4,200 Hz. What is the longest wavelength of sound produced by a piano? (The speed of sound in air is approximately 343 m/s.) (in m) A 9.80 B C D E F G H A massive piston traps a fixed amount of helium gas as shown. After being brought to point (a) the system equilibrates to room temperature. The gas is then cooled ISOBARICALLY compressing the gas to half of its original volume (b). 10. the pressure Pb Pa.

3 11. The entropy of the gas at "b" is the entropy of the gas at "a". 12. The temperature Tb Ta. 13. The internal energy Ub Ua. 14. A large steam pipe is covered with 1.5-cm-thick insulating material of thermal conductivity 0.21 J/(s m C). How much energy (in J) is lost every second when the steam is at 220 C and the outside of the pipe has a temperature of 20 C? The pipe has a circumference of 7.5 m and a length of 50 m. Neglect losses through the ends of the pipe. A 6.56x10 5 B 7.67 x 10 5 C 8.97 x 10 5 D 1.05 x 10 6 E 1.23 x 10 6 F 1.44 x 10 6 G 1.68 x 10 6 H 1.97 x , At high noon, the Sun delivers 1.1 kw to each square meter of a blacktop road. If the hot asphalt loses energy only by radiation, what is its equilibrium temperature (in degrees Celsius) of the road surface? A 78.4 B 88.6 C D E F G H A figure skater is spinning with her arms and one leg extended as far as she can. She then pulls them in tight to her body. As her position contracts, 16. her angular velocity. 17. her rotational kinetic energy. 18. her angular momentum. 19. her moment of inertia. 20. Two sounds have intensities 4 x 10-3 and 6.5x 10-7 W/m 2. What is the magnitude of the difference in intensity levels between the two sounds in db? A B C D E F G H 89.15

4 21. After landing, a jet airplane comes to rest uniformly (the acceleration is constant) in 11.5 seconds. The aircraft rolls m. What was the landing speed? (in km/hr) A B C D E F G H Consider the graph of force, F, vs. time, t shown above. The hashmark on the vertical axis denotes a value F0=30 N. Find the velocity of a 4.3-kg object as it moves from t = 0.0 to t = 6.0 s after starting at rest. (in m/s) A 5.04 B 6.71 C 8.92 D E F G H A rock is dropped from outer space (initial velocity=0) at a radius R from Earth's center. It is recorded moving at a speed 8368 m/s when it strikes the surface of the Earth. What was R? (in m) (Ignore the air resistance felt during the last few miles of the approach to the planet) R earth = 6:38 x 10 6 m, M earth = 5:98 x kg. (in m) A 4.75x10 6 B 5.94 x 10 6 C 7.42 x 10 6 D 9.28 x 10 6 E 1.16 x 10 7 F 1.45 x 10 7 G 1.81 x 10 7 H 2.27 x Two wires support a beam of length L=20 m and mass 330 kg as shown in the figure above. A box of mass 220 kg hangs from a wire which hangs from the beam a distance x=15 m away from the left edge of the beam. What is the tension in the RIGHT support wire? (in N) A 1062 B 1540 C 2233 D 3237 E 4694 F 6806 G 9869 H 14311

5 25. A vicious gorilla named Donkey Kong who is perched high in a tree spots the love of his life, a Spartan football player who, as luck would have it, has the same weight as Donkey Kong. Donkey Kong swings from a vine, beginning at an angle θ A and sweeps up his football player when the vine is vertical. He then swings upwards to a final angle of θ D. The points B and C refer to the instants just before and after he latches onto the linebacker. 26. The mechanical energy (kinetic+potential) of Donkey Kong at "A" is the mechanical energy of the gorilla+linebacker at "D". 27. The mechanical energy (kinetic+potential) of Donkey Kong at "B" is the mechanical energy of the gorilla+linebacker at "C". 28. Donkey Kong's momentum at "B" is the momentum of the gorilla+linebacker at "C". 29. The mechanical energy (kinetic+potential) of Donkey Kong at "A" is the mechanical energy of the gorilla at "B". 30. An immersion heater has a power rating of 1300 watts. It is used to heat water for coffee. How many minutes are required to heat liters of water from room temperature (20 C) to 90 C? A 30 B 40 C 53 D 70 E 94 F 125 G 166 H If 1.0 cubic meters of a building material weighs 6.5x10 4 N and a column of the material collapses under its own weight if the column is taller than 882 m, what is the compression strength (in Pa) of this material? (the maximum pressure that can be withstood by the material) A 7.78x10 6 B 1.04 x 10 7 C 1.38 x 10 7 D 1.83 x 10 7 E 2.44 x 10 7 F 3.24 x 10 7 G 4.31 x 10 7 H 5.73 x 10 7

6 An incompressible fluid moves through the pipe shown above from RIGHT to LEFT. The pipe narrows from a diameter of 5 cm at "A" to a diameter of 3 cm at "B". (Assume non-viscous laminar flow). 32. Then density of the fluid at "A" is the density of the fluid at "B". 33. The amount of fluid that passes "A" in one second is the amount of fluid that passes "B" in one second. 34. The pressure at "A" is the pressure at "B". 35. The speed of the fluid at "A" is the speed of the fluid at "B". 36.A gas is taken through the cyclic process described by the figure above. How much work (in J) was done by the gas during the expansion from A to B. A 4000 B 8000 C D E F G H 32000

7 A massive piston traps a fixed amount of helium gas as shown. After being brought to point (a) the system equilibrates to room temperature. Weight is then added ADIABATICALLY compressing the gas to half of its original volume (b). 37. The pressure Pb Pa. 38. The temperature Tb Ta. 39. The internal energy Ub Ua. 41. The entropy of the gas at "b" is the entropy of the gas at "a". 42. A train speeds around a curve with a radius of curvature of 1.41 km. If the acceleration experienced by the passengers is to be less than 0.1 g, find the maximum acceptable speed. (in km/hr) DATA: g = 9.81 m/s2 A 85.7 B C D E F G H Some asteroid named "Briggie" has been discovered revolving around the Sun on a circular orbit with at a radius of 2.86E+ 11 m. What is the period of Briggie's orbit? (in years) DATA: The radius of Earth's orbit is 1.50E+11 m. A 2.10 B 2.63 C 3.29 D 4.11 E 5.14 F 6.42 G 8.03 H 10.03