NSCI 3001      Name ______________
Quiz 2

1. If equal masses of copper and water are heated from 10°C to 20°C
a. more heat will be required for the copper
b. more heat will be required for the water

c. the same amount of heat will be required for each

2. If a mass of hot metal shot is dumped into a cool cup of water and allowed to reach a final temperature
a. the amount of heat lost by the metal shot is equal to the heat gained by the water

b. the heat loss by the metal shot is greater than that gained by the water
c. the amount of heat gained or lost by the copper and water are not related since they are very different substances

3. When you measure the temperature of an object with a thermometer, this temperature is a measure of
a. the total energy of the molecules of the object
b. the potential energy which holds the molecules together
c. the energy of the motion of the molecules

d. the amount of heat possessed by the object

4. The amount of heat required to increase the temperature of one gram of water by 1°C is called a calorie. The amount of heat required to melt a gram of ice at 0°C into a gram of water at 0°C is
a. much more than a calorie

b. much less than a calorie
d. nonsense! You can't have water and ice both at 0°C

5. If you have  a piece of wood and a piece of metal at the same temperature, 0°C, which would feel colder to the touch and why?

Even though the wood and metal are at the same temperature, the metal has higher thermal conductivity. This implies that it will conduct heat from your finger faster and feel colder.

6. A refrigerator
a. produces cold
b. causes heat to vanish
c. removes heat from a region and transports it to a warmer region
d. changes heat to cold

7. You connect two bulbs together and to a battery and observe that both light up. If you unscrew one bulb and the other goes out as well, this means that the bulbs were connected in
a.  series

b. parallel
c. can't tell from this information

8. Appliances in household circuits are wired in
a. series
b. parallel

c. both series and parallel

9. If you measure a voltage of 12 volts across a resistor at the same time that you measure 2 amperes of current through it, the resistance of the resistor is
a. 24 ohms
b. 1/6 ohms
c. 6 ohms

10. If you measure a voltage of 12 volts across a resistor at the same time that you measure 2 amperes of current through it, the power being used in the resistor is
a. 24 watts

b. 1/6 watt
c. 6 watts

11. From your exposure to the nature of metals in the geology, chemistry and physics portions of the class, state your understanding of why metals conduct electricity well while most other substances don't.

The outer or valence electrons in metals may move freely through the material, whereas all electrons are tightly bound to their atoms in insulating materials.

12. Why must there be two connections to a battery and to a light bulb?

The flow of current in a battery-powered circuit is analogous to the flow of water in a pump-powered loop of pipe - the wires of the circuit must make a complete loop for the current to flow continuously.

13. Two like electric charges
a. always attract each other
b. always repel each other
c. neutralize each other
d. have no effect on each other
e. must be neutrons.

14. The force which holds atoms together to form molecules is
a. electrical
b. magnetic
c. gravitational
d. mystical

15. Electrons flowing in a wire is analogous to water flowing in a pipe. "Electric current" is analogous to the volume flowrate of the water, and voltage is analogous to
a. pressure
b. resistance
c. amount of water
d. work
e. velocity of flow

16.  A device which transforms electric energy into mechanical energy is a
a. motor  c. transformer
b. generator  d. magnet

17. In the use of electricity in your home, it can be said that
a. electric charge and electric energy are used to operate the appliances
b. electric charge is taken in at a high voltage like 120 volts and the energy is used, after which the electric charge is transferred to the earth at 0 volts.
c. electric charge flows through the appliances without be affected in any way and is returned to where it came from.

18. The velocity of a sound wave depends upon the
a. frequency of the wave
b. amplitude
c. pitch of the sound
d. medium through which it travels

19. The speed of sound in air is 340 m/s. The wavelength in air of a sound wave of frequency 170 Hz is
a. 2 m

b. 0.5 m
c. 4 m
d. 510 m

20. Light rays coming from a fish under water and entering the air at an angle other than 90°
a. will be bent downward toward the water surface

b. will be bent upward toward the vertical
c. will not be bent
d. may be bend upward or downward, depending upon the color of the light

21. The property of light which makes possible the formation of clear images by the eye is
a. reflection
b. refraction

c. diffraction
d. interference

22. A tube is filled with water and then the water is gradually lowered while sounding a 1000 Hz tuning fork above the tube. The sound becomes louder when the distance to the water surface is 8.5 cm, showing that the air column resonant frequency is the same as the tuning fork frequency. Neglecting end corrections, this tells you that the sound wavelength is about
a. 8.5 cm
b. 17 cm
c. 25.5 cm
d. 34 cm

23. To accomodate for viewing close objects, the eye's lens must change its
a. focal length

b. image distance
c. aperture
e. iris opening

24. For a normal eye, parallel light beams would be focused to a dot on the retina. Describe what happens in the eye of a nearsighted person and how you correct nearsightedness.

In the nearsighted eye, light is refracted too much and parallel incident rays are made to focus before they reach the retina. Nearsightedness is corrected with a negative lens which cancels the excess focusing power.

25. Blue light differs from red light in that
a. its intensity is greater
b. its frequency is higher

c. its wavelength is longer
d. its quantum energy is lower

26. Physiological damage from x-rays is fundamentally different from that caused by microwaves because
a. the x-rays cause ionization and the microwaves cannot
b. the total power you get from microwaves is higher
c. microwaves are electromagnetic waves and xrays are not
d. microwaves have shorter wavelengths

27. The color you would get by mixing equal amounts of green and red light would be
 a. yellow b. white c. blue d. magenta

28. The color you would get by mixing equal amounts of yellow and blue light would be
a. red
b. white

c. blue
f. magenta

29. Name two similarities and two differences in the properties of sound and light.

Since both sound and light are waves, they have a number of common properties. Each has wavelength, frequency, and each experiences reflection, refraction, diffraction and interference. They are however very different in many respects: sound must have a medium to travel in, light can travel through empty space. Light is much faster. Light is electromagnetic in nature, while sound is mechanical.

30. When a real image of an object is formed on a screen by a lens, the image must be

a. inverted

b. larger than the object
c. smaller than the object
d. none of the above is necessarily true.

31. You are told that your electric water heater is almost 100% efficient in using the electric energy to heat water. This is misleading because

a. It takes about three units of fuel to generate one unit of electrical energy.

b. More heat is lost through the heater walls than you might think
c. Gas water heaters use the gas more efficiently than the electric heater uses the electricity.

32. If a heat engine operates at 600K (hot reservoir) and gives off heat at 300K its maximum efficiency is

a. 50%
c. 100%
b. 200%  d. 95%
This limitation is placed on it by
e. friction

f. the second law of thermodynamics

g. the conservation of energy principle
h. the General Motors Corporation

33. If an air column musical instrument like a flute is made shorter, then its pitch will be
a. higher because the wavelength is longer and the sound speed faster
b. lower because the wavelength is shorter and the sound speed is the same

c. higher because the wavelength is shorter and the sound speed is the same

d. higher because the wavelength is shorter and the sound speed is higher

34. The changing granulation of the solar surface represents.
a) absorbing regions of chlorine gas
b) convection cells of rising and sinking gases

c) electron transitions between the 3 and 2 orbital in Hydrogen
d) blurred vision of an astronomer after being on a Corona binge

35. How does the temperature and magnetic field in a sunspot compare to its general surroundings?
a) hotter with stronger magnetic field
b) hotter with weaker magnetic field
c) cooler with weaker magnetic field
d) cooler with stronger magnetic field

e) similar temperature and magnetic field

36. The "energy currency" for the cell is:
d. actin
e. myosin
f. ATP

g. glucose

37. All of the following molecules are commonly  used by living things for energy storage except:
e. glycogen
f. lactic acid

g. cellulose
h. starch

38. Muscle contraction is an example of:
a. mechanical work

b. electrical work
c. nuclear work
d. synthetic work

HyperPhysics***** NSCI 3001