Exam 4. Today last regular day Tomorrow (Saturday) is the late day Your study guide is the homework!

Transcription

1 Exam 4 Today last regular day Tomorrow (Saturday) is the late day Your study guide is the homework!

2 Final Exam All Finals week in the RB Same format, same rules as midterms, but no free response - one page of notes - bring a calculator, scratch paper, pencils, erasers - 16 multiple choice Problems from midterms and practice exams with different numbers and names

3 Checking your answers Don t plug in numbers until the end! Do answers make sense? What happens when you change a variable? Check units Try different ways to work problem Work it backwards

4 Course Evaluations extra credit 0.5% on your final class score Make sure you check the option to show me your name (I won t know what your responses were, and I won t see any responses until grades are submitted).

5 Unit 1 Review Fluids density Pascal s law (pressure vs. depth) Equation of continuity Buoyant force-archamedes Bernoulli s (pressure, velocity, depth)

6 Sound Waves Transverse vs. longitudinal waves Frequency, period, wavelength Antinodes, nodes Doppler effect Pipes and strings Resonances

7 1 st Midterm Question 15

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10 1 st Midterm Question 7

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13 1 st Midterm Question 4

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16 WHO ARE YOU? WHO IS THAT PERSON SITTING NEXT TO YOU?

17 Unit 2 Review Ideal Gas PV=nRT Watch units W work done by gas vs. on gas Adiabatic, constant V, T and P Thermal equilibrium Entropy

18 Unit 2 Review Heat --Internal energy degrees of freedom 1st and 2nd laws of thermodynamics Temperature change: Q=mc T Phase change: Q=mL Radiation, convection, conduction

19 2 nd Midterm Question 15

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21 2 nd Midterm Question 2

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23 A block of wood floats in a bowl of water. On top of the block there is a lead weight attached. The block turns over so that the lead weight is under water still attached to the floating block. When this happens, the water level in the bowl (a) goes down. (b) remains unchanged. (c) goes up.

24 A block of wood is glued to the bottom of a container. Water in the container completely covers the block. The glue dissolves and the block rises to the top where it floats. When this happens, the water level (a) goes up. (b) remains unchanged. (c) goes down.

25 Discussion question: A glass is filled to the top with ice and water. When the ice melts, where is the water level? A. Above the rim so it spills over. B. At the rim same place as before. C. Below the rim

26 Blood flows through a coronary artery that is partially blocked by deposits along the artery wall. Through which part of the artery is the flow speed largest? A. The narrow part. B. The wide part. C. The speed is the same in both parts.

27 Blood flows through a coronary artery that is partially blocked by deposits along the artery wall. Through which part of the artery is the pressure the lowest? A. The narrow part. B. The wide part. C. The speed is the same in both parts.

28 A tornado moves over a house and causes the windows to explode. They will explode (a) outward. (b) inward.

29 A sinusoidal wave propagates on a string. The tension in a string remains fixed, but the frequency is doubled. What happens to the wavelength? (a) The wavelength is halved. (b) The wavelength remains unchanged. (c) The wavelength is doubled.

30 A flute is played with helium inside instead of air. The wavelength (inside the flute) of the fundamental note (a) decreases. (b) remains unchanged. (c) increases.

31 Two strings, one thick and the other thin, are connected to form one long string. A wave travels along the string and passes the point where the two strings are connected. Which of the following does not changes at that point: A. frequency B. velocity C. wavelength

32 You hear a violinist playing a series of notes of decreasing wavelength on a particular string. As the wavelength decreases, the wave speed in the string A. Decreases B. Increases C. Stays the same

33 A string fastened at both ends has a length of 1.0 m. Two possible wavelengths for standing waves are A. 4 m and 2 m B. 4 m and.5 m C. 2 m and.66 m D. 3 m and.66 m E. 3 m and 2 m F. 3 m and.5 m G. 2 m and.20 m

34 Two tuning forks have frequencies 440Hz and 438Hz. When they are both struck, a listener hears the intensity vary in time (i.e. wa - wa - wa -...). What is the period of this intensity variation?

35 A stationary observer hears a pitch from a source that moves towards him, the observed frequency will be the source frequency A. Lower than B. The same as C. Higher than

36 In an ideal gas, if you double the volume of the container, while keeping the temperature and the number of molecules the same, the pressure in the gas A. Decreases B. Stays the same C. Increases

37 Suppose we have two jars of gas, one of helium and one of oxygen. If both jars have the same volume, and the two gases are at the same pressure and temperature, which jar contains the greatest number of molecules? A. Jar of helium B. Jar of oxygen C. Both jars contain the same number. Consider both gases to obey the ideal gas law. Also note that the mass of an oxygen atom is greater than the mass of a helium atom.

38 C water =4186 J/kg o C C gold =129 J/kg o C Which heats up faster using the same heat source? A. 1 kg water B. 1 kg gold C. They both heat up at the same rate. Q mc T Q is energy transferred

39 Put 100g Al at 100 o C into 500g water at 20 o C. What is the final T? c Al =900 J/kg o C c H2O =4186 J/kg o C What will the final T be? A. 100 o B. 97 o C. 20 o D. 23 o E. 60 o

40 The first law of thermodynamics E int = Q + W Change of internal energy = heat put into system + work done on system The internal energy of an ideal gas depends only on the temperature of the gas.

41 True or False: Given two different objects, the one with the higher temperature contains more heat. (a) T (b) F

42 The path shown below is adiabatic (Q = 0). The change in internal energy of the gas is P V A. Positive B. Negative C. zero

43 In the path shown, the change in internal energy of the gas is P A. Negative B. Positive C. Zero V

44 In the path shown below, the gas returns to its original state. The net change in internal energy is P A. Positive B. negative C. zero V

45 In the path shown below, the heat Q put into the gas is (a) negative. (b) zero. (c) positive. P V

46 In the path shown below, the gas returns to its original state. The heat put into the gas is P V A. Positive B. negative C. zero

47 One of the P-V curves below is for an isothermal process. The other is for an adiabatic process. Which is adiabatic? P B A V

48 Two gases in separate containers have equal volumes, equal numbers of molecules, and the same internal energy E int. However, one gas is monatomic and the other is diatomic. The pressure of the diatomic gas is A. Less than that of the monatomic gas. B. The same of that of the monatomic gas. C. Greater than that of the monatomic gas.

49 The second law of thermodynamics says for a heat engine A. You can t get more work energy out than you consume in heat B. You can t get out all of the heat energy as work C. You will get out more work energy than you consume in heat