Final Exam – Physics 201 –

Dr. Joseph E. Johnson – December 12, 2003

No one is permitted to leave early because it disturbs those who are still taking the exam

You have 2 hours maximum. You will keep your question sheets.

Write in your name and student number and also bubble your student number carefully.

Keep your answer sheet and working papers covered at all times. G = 6.67E-11 in MKS

For each choice, 'e' is none of the above or cannot be solved or answered with this data.

All values are in MKS units unless otherwise noted.

If your answer rounds off to an answer that is given, then it should be your choice.

For example, if I were to ask for the value of Pi, then '3' would be a correct answer.

The universal gas constant R = 8.314 Joule/(mole*K)

The latent heat of fusion of ice is 3.34E5 J/kg

For g in the metric system, use the value rounded to the nearest integer.

Coefficient of linear expansion of aluminum = 2.4E-5 (degrees C^-1)

Heat of fusion of water is 3.33E5 J/kg

Heat of vaporization of water is 2.26E6

Stefan Boltzman constant is 5.7E-8 W/(m^2 * K^4)

Moment of inertia of a sphere = (2/5) M R^2

______

  1. A plastic 3 liter bottle of water will have a mass of about
  2. 30 kg b.% 3 lbs c. 5 kg d. 9 lbs
  3. The prefix 'Tera' means multiply by
  4. 10-12 b. 10-15 c. 109 d. ~1012
  5. Correct use of significant digits for 3.4 * 2.8546 is
  6. ~9.7 b. 10 c. 9.7056 d. 9.71
  7. Recalling that an inch is exactly 2.54 cm, then convert 5 yards to meters:
  8. 457.2 b.% 4.572 c. 38.1 d. 3.81

Ignore all air friction in the following problems:

  1. A baseball is thrown straight up from ground level at a speed of 128 ft/s
  2. What is the acceleration at the highest point (ignore the sign) in ft/s^2:
  3. 0 b. % 32 c. 64 d. 128
  4. How high will the ball go in ft?
  5. 16 b. 32 c. 64 d % 256
  6. How long will it take the ball to get back down to the ground (in sec)?
  7. 1 b 2 c 4 d % 8
  8. What will be the velocity in ft/s when the ball hits the ground again?
  9. 16 b. 32 c. 64 d % 128
  10. A vector has components Ax = 3m and Ay = 7 m. What is its magnitude in m?
  11. %7.6 b. 8.9 c. 5 d. 137
  12. What is the angle of the vector with the x axis in the last problem (in degrees)?
  13. 44.51 b. 58.40 c. 62.1 d % 66.8
  14. An airplane flies with an airspeed of 200 mph directly north but there is the wind is blowing to the southeast at 50 mph. What is the actual speed of the plane relative to the ground in mph?
  15. %168 b. 172 c. 178 d. 181
  16. What is the angle of the planes direction away from east in degrees in the last problem?
  17. 67 b. % 78 c. 82 d. 87
  18. If a force of 62 Newtons is applied to a mass of 4 kg, the acceleration in m/s^2 is
  19. 6.5 b. 104 c. %15.5 d. 0
  20. A mass of 4 kg rests on a table and is attached by a massless wire to a mass of 8 kg that hangs over the edge of the table via a pulley. If there is no friction, what is the acceleration of the system in m/s?
  21. %6.67 b. 16 c. 10 d. 8
  22. What is the tension in the string in Newtons?
  23. %26.67 b. 44.5 c. 83 d. 16
  24. 1. A 6 ft 6 in length is laid out on the curve of a circle of radius 4 feet. What is the subtended angle in radians: a 7.3 b. %1.6 c. 1.4 d. 0.72
  25. An object of mass 4 kg revolves in a circle of radius 2 meters attached by a massless string to the center. There is no gravity and no friction. It makes a complete turn every 16 seconds. Answer in MKS units (ie metric):
  26. What is the angular velocity? a. 2 b. 4 c. 0.8 d.% 0.4
  27. What is the centripetal acceleration? a. 1.23 b.% 0.3 c. 6.28 d. 5.11
  28. What is the tangential velocity? a. % 0.8 b. 3.14 c. 6.3 d. 1.57
  29. What is the period of the revolution? a. 8 b. % 16 c. 1/16 d. 1/2
  30. What is frequency? a. 8.666 b. 2.5 c. %0.0625 d. 0.125
  31. What is the centripetal force? a. 5 b. 10 c. %1.2 d. 8
  32. The acceleration due to gravity on a planet that is four times the mass and twice the radius of earth would be what factor times g on our planet earth. a. %1 b. 4 c. 32 d. 64
  33. When a spring is compressed a distance of 4 m, the force it exerts is 24 Nt. What is the spring constant? a. 48 b. 3 c. 0.33 d. % 6
  34. How much potential energy did it take to compress the spring in the last problem? a.% 48 b. 0.33 c. 3 d. 24
  35. A football player (Bob) who has a mass of 120 kg moving at 8 m/s hits a stationary player (Jim) who has a mass of 240 kg. Assume that Bob and Jim are a single tangled entity after the collision (stuck together). What is their velocity? a. 8.4 b. 8 c. %2.67 d. 4.8
  36. After the game, Bob decides to run up the stadium steps and goes up an height of 40m in a time of 4 seconds. How much work did he do? a. 12,000 b. 24,000 c.% 48,000 d. 36,000
  37. How much power did this require in Watts? a. 900 b.1800 c. %12,000 d. 8,000
  38. A 100 Watt light bulb was left on all night and burned for 12 hours. How many kilowatt hours of energy did it consume. a. 2.35 b. 15 c. % 1.2 d. 54
  39. Estimate the cost of the last problem by choosing the closest value. a %.$0.10 b $1 c.$10 d. $0.01 e. $0.001
  40. If an aluminum bar of length 28 ft is heated 36 degrees Celsius, what is the change in length in ft ? a.1.2 b.% 2.4E-2 c. 4.2E-3 d. 1.2E-2
  41. How much heat in Joules is required to melt a 95 kg block of ice at zero degrees Celsius into water at zero degrees Celsius. a. 1.7E5 b. 1.5E7 c. 5.7E6 d.%3.16E7
  42. How much power in Watts is radiated by a surface of 6 square meters at the temperature of 300 Kelvin and an efficiency (emissivity) of 0.4. a. 639 b. 369 c. 963 d. %1108
  43. How many Calories are required to heat 81 kg of water 18 degrees Celsius? a. 232 b. 323 c.23 d. % 1458
  44. A sphere of mass 5kg and radius 9 m is rolling on a flat plane at a velocity of 3 m/s.
  45. What is its moment of inertia? a. 81 b. %162 c. 18 d. 241
  46. What is its angular velocity ? a. 4.3 b. 0.5 c. 1.5 d. %0.333
  47. What is its rotational kinetic energy in Joules ? a. 27 b. %9 c. 4 d. 13
  48. A 10 kg cube of gold measures 2cm on each side. What pressure in Pascals does the face of the cube feel that supports the cube on a table. a. 0.3125 b. 125 c. 3125 d. %250,000
  49. A hydraulic lift uses oil which has a density of 500 kg/m^3 and has pistons of area 0.5 and 4 square meters. How much weight in Newtons can the lift raise if 20 Newtons is applied to the smaller of the two pistons. a. 80 b. 100 c. 40 d. %160
  50. A bridge has a mass of 4000 kg and a length of 40 m. A pile of bricks of mass 500 kg is located 10 m from one end of the bridge. What force in Newtons does that end of the bridge support? a % 23,750 4 b. 24,000 c. 350,000 d. 29,863
  51. The temperature outside is 25 degrees for 12 consecutive hours. How many heating degree days have accumulated? a.15 b.% 20 c. 30 d. 60
  52. A wall measures 8 ft high by 40 ft long without windows. If the wall was standard without insulation (ie R=3.5) and then was filled with an R=11 insulation, how many BTUs per hour would be lost through the wall if there is a 40 degree temperature difference between the inside and outside? a. 72,000 b. % 883 c 1420 d. 2800
  53. How much heat would it have lost if the entire wall were just a single sheet of plate glass ? ? a. 72,000 b. 12,800 c. 14200 d. 28,000
  54. If one has 280 grams of N2 (ie molecular oxygen) then how many moles does one have?. a. 2 b. 6 c. 8 d. %20
  55. In the last problem, how many molecules does one have ? a. 3.6E24 b.% 1.2E25 c. 2.4E24 d. 6E23
  56. If the volume of an ideal gas is quadrupled, while the pressure is constant, and the original temperature was 200 K, then what was the final temperature? a. 50 b. 100 c. 400 d.~ 800
  57. The maximum thermodynamic efficiency that can be obtained in a coal plant where the boiler temperature is 777 degrees in percent is ? a. 40 b. 35 c. 81 d.% 61
  58. The standard total efficiency of a modern coal or nuclear plant in percent is ? a.% 40 b. 20 c. 81 d. 61 e. 50
  59. A man decides to capture sunlight by photocell in SC using a system which is 15% efficient and 60 square meters attached to his roof. On the average over a year, how much power will the system put out ? a. 900 b. 450 c. 455 d. %1800
  60. If we burn about 40 tons of a chemical fuel, how much energy will we generate in BTUs? a. 4E18 b. 4E6 c. 4E7 d. 4E15 e. % 4E8
  61. The intensity of a sound wave is 1E-5 watts per square meter. How much is this in decibels ? a. %70 b. 30 c. 40 d. 80
  62. If one note on the piano is 400 Hz then what is the frequency of the next adjacent note above it (ie a half step up)? a. 412 b. 416 c. 420 d. % 424
  63. The human body normally takes what function of an external stimulus? a. the exponent b.% the logarithm c. the cosine d. the square
  64. If the frequency 300 MHz is heard on the radio, what is the wavelength of the electromagnetic radiation? a. 10m b.% 1m c. 0.1m d. 0.0001m

Consider an ideal gas consisting of four moles of O2 molecules for the following questions:

  1. How many molecules are there? a. 2.4E23 b. 6.0E23 c. 4.8E24 d. ~2.4E24
  2. How much volume in moles does this gas occupy in Liters at standard temperature and pressure? a. ~89.6 b. 22.4 c. 44.2 d. 32.0
  3. If the pressure is doubled, and the temperature is constant then the volume is what factor times the original? a. 2 b. ~ ½ c. 1/4 d. 4
  4. If the pressure is doubled and the temperature is quadrupled, the volume is what factor times the original? a. ~ 2 b. ½ c. 1/4 d. 4
  5. How much does this gas weigh in grams? a. 32 b. 16 c. ~128 d. 1024
  6. What name is associated with the laws governing an gas law? a. Charles b. Boyle c. Gay-Lussac d. ~All three
  7. Comparison of the ideal gas law to computations from kinetic theory gives a meaning to temperature as proportional to a. ~the random kinetic energy b. the total random kinetic energy c. the total random momentum d. the average entropy
  8. The distribution of velocities in an ideal gas is given by an equation developed by a. Maxwell b. Boltzman c. ~ Both d. Neither but rather another person
  9. The first law of thermodynamics is equivalent to the conservation of energy and gives the change in internal energy U as a. Q+W b. ~Q-W c. W-Q d. S+Q
  10. If a nuclear power plant could operate at a temperature of 900 degrees K then what would be the associated maximum efficiency via a Carnot cycle? a. 33.3% b. 50.0% c. ~66.7% d. 25%
  11. A process that takes place at constant pressure is called a. isothermal b. isochoric c. ~ isobaric d. adiabatic
  12. A process that takes place at constant volume is called a. isothermal b. ~isochoric c. isobaric d. adiabatic
  13. The coefficient of performance of a refrigerator, when the an amount of heat 50 Calories is moved, using 40 Calories of Work to add a total of 90 Calories of heat to a high temperature reservoir is a. ~1.25 b. 0.80 c. 0.556 d. 2.25
  14. If the system in the last problem is reversed to perform as a heat engine the coefficient of performance of the heat pump would be a. 1.25 b. 0.80 c. 0.556 d. ~2.25
  15. A student takes a 5 kg block of ice at 0K and place it on a large rock outcropping and watches the ice melt. What is the entropy change (ignore sign) of the ice (water)? a. 423 b. 5101 c. ~ 6117 d. 7116 e. 12,449 (choose the closest answer)
  16. If the source of heat (the rock) is very massive and remains at a constant 21 C then what would be the change in entropy of the rock (ignore sign) ? a. ~ 5680 b. 6058 c. 568 d. 8560 e. 5566 (choose the closest answer)
  17. Which entropy change is negative ? a. ~the rock b. the ice c. neither d. both
  18. The measure of order in a system is called a. entropy b. chaos c. ~information d. heat
  1. If a force of 10 Newtons distorts a spring by a distance of 2 m from equilibrium, with a mass of 4kg attached, in a time of 5 seconds then the spring constant is a. 20 b. ~ 5 c. 2 d. 10
  2. How much energy is stored in the system in the last example? a. 20 b. 5 c. 2 d. ~ 10
  3. What is the angular frequency of the oscillation when the system is released? a. ~1.12 b. 2.12 c. 1.22 d. 1.21
  4. If a pendulum of length 2 meters swings on earth it will have a period of about

a. ~ 2.8 b. 1.26 c. 0.80 d. 14

  1. If friction is present then the cos oscillation is multiplied by a factor of a.~ e-t b. et c. cos(t + ) d. cos(t - )
  2. The equation that gives the force as a function of the distortion from equilibrium is called who’s law? a. Boltzman’s b. Pascal’s c. ~ Hooke’s d. Maxwell’s