Final Exam: December 14 (Wed) 1:30 – 4:30 pm

1. The Final Exam is cumulative Final Exam: December 14 (Wed) 1:30 – 4:30 pm Room assignments: check website Please resolve any grade-related issues as soon as possible (excused absences, DR, homework, etc.). Check your grades in the gradebook.

2. The MAIN reason I signed up for Phys 140 instead of another course is • I thought it would be interesting • I thought it would be an easy “A” • I thought it would not be much work • I thought it would be fun • Other

3. A battleship simultaneously fires two shells toward two enemy ships, one close by (A), one far away (B). The shells leave the battleship at different angles and travel along the trajectories indicated below. Which of the two enemy ships gets hit first?

4. Two light bulbs are connected in series to a battery. When a wire is connected across light bulb 1, light bulb 2 2 1 (A) glows more brightly (B) glows more dimly (C) does not change (D) goes out

5. Two uniformly charged spheres are fastened to pucks on an air hockey table. The charge on sphere 2 is three times the charge on sphere 1. Which force diagram correctly shows the magnitude and direction of the electric forces: (A) (C) (D) (B)

6. A box, with its center-of-mass off-center as indicated by the dot, is placed on an inclined plane. In which of the four orientations shown, if any, does the box tip over?

7. A ladybug sits at the outer edge of a merry-go-round, and a gentleman bug sits halfway between her and the axis of rotation. The merry-go-round makes a complete revolution once each second. The gentleman bug’s angular velocity is A. half the ladybug’s. B. the same as the ladybug’s. C. twice the ladybug’s. D. impossible to determine

8. A 10-kg weight is suspended from the ceiling by a spring. The weight-spring system is at equilibrium with the bottom of the weight is about 1 m above the floor. The spring is then stretched until the weight is just above the eggs. When the spring is released, the weight is pulled up by the contracting spring and then falls back down under the influence of gravity. On the way down, it (A) smashes the eggs (B) reverses its direction far above the eggs (C) reverses direction exactly when it reaches the eggs

9. A nitrogen nucleus has 15 nucleons. The atomic number of nitrogen is 7. The number of protons in this nucleus is (A) 7 (B) 8 (C) 15 (D) 22

10. A tank circuit is built from which components? (A) Battery and inductor (B) Inductor and capacitor (C) Capacitor and resistor (D) Resistor and battery

11. An MRI device uses (A) Magnets and gamma rays (B) Magnets and beta rays (C) Magnets and alpha rays (D) Magnets and radio waves

12. A CT scan uses (A) X rays (B) Microwaves (C) Delta rays (D) Lasers

13. When an air conditioner cools a room, it (A) decreases the air pressure in the room. (B) decreases the entropy in the room. (C) decreases the entropy outside of the room. (D) violates the second law of thermodynamics.

14. The musical scale where each successive note has a frequency bigger by a factor of the twelfth root of 2 (approximately 1.06) is called the (A) well-done scale. (B) well-tempered scale. (C) equal-tempered scale. (D) hot-tempered scale.

15. The tiny filament in a 150 W light bulb emits more power than your whole body. How is that possible? • The power emitted by an object depends strongly on temperature. • Electricity is a better power source than food. • The filament has a much higher emissivity than a human body.

16. i>clicker question Modern well-insulated windows are coated with a material that • reflects IR radiation • absorbs IR radiation • reflects UV radiation • absorbs UV radiation Phys 150 Lecture 27

17. i>clicker question Modern well-insulated windows are coated with a material that • reflects IR radiation –ITO (Indium Tin Oxide) • absorbs IR radiation • reflects UV radiation • absorbs UV radiation – ordinary glass Phys 150 Lecture 27

18. i>clicker question In the winter, if you turn down your thermostat at night (but put it back to normal during the day), you will • use less energy • use more energy • use less energy at night but more during the day • pay less for energy because natural gas is more expensive to at night Phys 150 Lecture 27

19. i>clicker question In the winter, if you turn down your thermostat at night (but put it back to normal during the day), you will • use less energy • use more energy • use less energy at night but more during the day • pay less for energy because natural gas is more expensive to at night - Heat loss is proportional to temperature difference between inside and outside Phys 150 Lecture 27

20. I hope that you had fun in PHYS 140! Keep in touch!

21. What is science / physics? • A picture of how the world works • Backed up by data • Predictive • Done by (relatively) normal people • Evolving • Useful for technology • Sometimes transformational for humanity

22. Big ideas • Newton’s laws • Work and conservation of energy • Mechanical advantage • Friction and Entropy • Mass and Weight • Heat • Phases of matter • Radiation and light • 2nd law of thermodynamics • Electromagnetic induction • Structure of atoms and nuclei

23. How things work • Bicycles • Air conditioners / refrigerators / dehumidifiers • Car engines • Light bulbs • Atomic clocks, GPS • Circuits, flashlights • AC power distribution • Generators, Motors • Radio, cell phones • Microwave ovens • Nuclear weapons and power • X-rays, CT scans, MRI, radiation therapy