Reference no: EM131032535
1. In which direction does internal energy flow between hot and cold object?
2. How does the specific heat capacity of water compare with the specific heat capacities of other common materials?
3. Why do substances expand when their temperature is increased?
4. Why does all of the water in a lake have to be cooled to 4oC before the surface water can be cooled below 4oC?
5. Suppose that the 1.3-km main span of the steel for the Golden Gate Bridge had no expansion joints. Show that for an increase in temperature of 20oC, the bridge would be nearly 0.3 m longer.
6. Which is greater: an increase in temperature of 1 Celsius degree or an increase of 1 Fahrenheit degree?
7. Why can't you expect all the molecules in a gas to have the same speed?
8. What was the precise temperature at the bottom of Lake Superior at 12:01 AM on December 31, 2013?
9. State whether water at the following temperatures will expand or contract when warmed a little: 0oC, 4oC, 6oC
10. A metal ball is just able to pass through a metal ring. When the Annette increases the temperature of the ball, however, it will not pass through the ring. What would happen if she instead increases the temperature of the ring rather than the ball? Discuss whether the size of the hole increases, stays the same, or decreases.
11. What happens to the volume of air as it rises? What happens to its temperature?
12. In what form does radiant energy travel?
13. Since all objects emit energy to their surroundings, why don't the temperatures of all objects continuously decrease?
14. In a 25 oC room, hot coffee in a vacuum flask cools from 75 oC to 50 oC in 8 hours. Explain why your prediction is that its temperature after another 8 hours will be 37.5 oC.
15. In lab you submerge 100 g of 40oC iron nails in 100 g of 20oC. water (the specific heat of iron is 0.11 cal/g/oC
Equate the heat gained by the water to the heat lost by the nails, show that the final temperature of the water becomes 22oC
Your lab partner is surprised by the result and says that since the masses of iron an water are equal, the final temperature should be closer to 30oC, halfway between. What is your explanation?
16. In a mixture of hydrogen and oxygen gases at the same temperature, which molecules move faster? Why?
17. A snow-making machine used for ski areas blows amixture of air and water through a nozzle. The temperature of the mixture may initially be well above the freezing temperature of water, yet crystals of snow are formed as the mixture is ejected from the nozzle. Explain how this happens.
18. Even though metal is a good conductor, frost can be seen on parked cars in the early morning even when the air temperature is above freezing. Provide an explanation.
19. If you were caught in freezing weather with only your own body heat as a source, discuss whether you'd be warmer in an Arctic igloo or a wooden shack.
20. Why does helium released into the atmosphere eventually disappear into space?
21. What are the four common phases of matter?
22. Distinguish between humidity and relative humidity.
23. Why doesn't the water at the bottom of a geyser boil when it is a 100oC?
24. Why doesn't energy added to boiling water increase the temperature of the water?
25. When will water boil at a temperature lower than 100oC?
26. How many calories are needed t change the temperatures o f1 g of water by 1oC? To melt 1 g of ice at 0oC? To vaporize 1 g of boiling water a 100oC?
27. Find the mass of 0oC ice that 10 g of 100 oC steam will completely melt.
28. Why do clouds often form above mountain peaks? (Hint: Consider the updrafts.)
29. Why is half-frozen fruit punch always sweeter than completely melted fruit punch?
30. Porous canvas bags filled with water are used by travelers in hot weather. Discuss why, when the bags are slung on the outside of a fast-moving car, the water inside is cooled considerably.
31. How does the law of conservation of energy relate to the first law of thermodynamics?
32. What is the relationship among heat added to a system, change in the system's internal energy, and external work done by the system?
33. What happens to the internal energy of a system when mechanical work is done on it?What happens to its temperature?
34. What condition is necessary for a process to be adiabatic?
35. What generally happens to the temperature of rising air? Of sinking air?
36. What is a temperature inversion?
37. Now does the second law of thermodynamics relate to the direction of heat flow?
38. What three processes occur in every heart engine?
39. What is the physicist's term for measure of amount of disorder?
40. The temperature of the Sun's interior is about 107 degrees. Does it matter whether this is degrees Celsius or kelvins? Explain.
41. What is the source of all waves?
42. What is meant by the period of a pendulum?
43. Which has the longer period: a short or a long pendulum?
44. In what direction are the vibrations relative to the direction of wave travel in a transverse wave?
45. In what direction are the vibrations relative to the direction of wave travel in a longitudinal wave?
46. What kinds of waves can show interference?
47. In the Doppler effect, does the frequency change? Does the wave speed change?
48. A skipper on a boat notices wave crests passing his anchor chain every 5 s. He estimates the distance between wave crests to be 15 m. He also correctly estimates the speed to waves. Show that this speed is 3m/s.
49. A grandfather pendulum clock keeps perfect time. Then it is relocated to a summer home high in the mountains. Does it run faster, slower, or the same? Explain.
50. Why is lightning heard before thunder is heard?
51. What is the relationship between frequency and pitch?
52. Why doesn't sound travel in a vacuum?
53. Distinguish between a compression and a rarefaction.
54. What is a reverberation?
55. What is the wavelength of a 340-Hz tone in room temperature air? What is the wavelength of 34,000-Hz ultrasonic wave in the same air?
56. A cat can hear sound frequencies up to 70,000 Hz. Bats send and receive ultra-high frequency squeaks up to 120,000Hz. Which hears the shorter wavelengths: cats or bats?
57. What does t mean to say that a radio station is "at 101.1 on your FM dial?"
58. Why can the tremor of the ground for a distant explosion be felt before the sound of the explosion can be heard?
59. A rule of thumb for estimating the distance in kilometers between an observer and a lightning stroke is to divide the number of seconds in the interval between the flash and the sound by 3. Is this rule correct? Discuss the reason for its correctness or incorrectness.
60. How does a high-pitch musical note relate to frequency?
61. What does a decibel measure?
62. Is the sound of 30 dB 20 times greater than the threshold of hearing, or 103 (a thousand) times greater?
63. What are the three principal classes of musical instruments?
64. Distinguish between analog and digital for how the sound signal is captured on phonograph records versus on a DVD?
65. Why are the bass strings of a guitar thicker than the treble strings?
66. Why do the same notes on a trumpet and on a saxophone sound different when both are played with the same pitch and loudness?