PHYSICS 1020 - Spring 1997

SOLUTIONS FOR FIRST EXAM
15 January 1997

(Correct solution is indicated by ``(*)'')

1. Earth has the shape of a football, rotating around its elongated axis.

   (a) True (b)(*) False

2. Planets can be recognized by the fact that they are always seen at the same position with respect to the background stars, but their brightness changes during the year.

   (a) True (b)(*) False

3. A microsecond is one millionth of a second.

   (a)(*) True (b) False

4. Most of the volume of an atom is occupied by its nucleus.

   (a) True (b)(*) False

5. If by some mechanism you could take away the fastest 10% of molecules from a liquid, the liquid's temperature would

   (a) rise (b)(*) drop (c) stay the same

6. Unlike liquids or solids, a given amount of gas can expand to fill a container of any size.

   (a)(*) True (b) False

7. One meter corresponds to approximately 40 inches.

   (a)(*) True (b) False

8. The apparent size of an object depends on the size of its image on the retina.

   (a)(*) True (b) False

9. Plasma is the rarest of all forms of matter.

   (a) True (b)(*) False

10. When a liquid boils, some of it evaporates and forms vapor bubbles which rise to the top of the liquid. This is what causes the bubbling of a boiling liquid.

    (a)(*) True (b) False

11. It is photosynthesis in plants which uses carbon dioxide and replenishes the oxygen content of our air.

    (a)(*) True (b) False

12. The air in our atmosphere is a mixture of oxygen and nitrogen, with small amounts of other gases.

    (a)(*) True (b) False

13. Helium was first discovered by analyzing the spectrum of light from very faint and distant stars.

    (a) True (b)(*) False

14. Adding cold water to your drink would cool it just as well as adding an equal amount of ice to it.

    (a) True (b)(*) False

15. ``Physics'' could best be described as the study of
    1. matter.
    2. energy.
    3. the absolute truths about the natural world.
    4. (*) the general principles underlying natural phenomena.
    5. the application of science to the needs of human beings.

16. In Copernicus' theory of planetary motion, retrograde motion is explained as
    1. the backward part of the planet's epicycle on its orbit around Earth.
    2. (*) a result of Earth's motion: as Earth passes another planet, that planet appears to move backward as seen against the background stars.
    3. due to the oscillatory back-and-forth motion of planets on their circular orbits around Earth.
    4. due to the irregular motion of the celestial sphere carrying the background stars.
    5. due to slowing down and speeding up of the Earth on its orbit around the sun.

17. Which of the following features of science is the most essential, i.e. that feature without which we should not call a field a ``science''?
    1. the use of mathematics;
    2. the use of quantitative measurements;
    3. the use of only those theories which are known to be true;
    4. the usefulness of its results for human well-being and technological progress;
    5. (*) the possibility of testing its predictions by experiment or observation, whereby they can be disproved (falsified);

18. According to Ptolemy's theory of planetary motion, the planets move in
    1. (*) circles-within-circles (epicycles on deferents) around Earth.
    2. circles around the sun.
    3. circles around Earth.
    4. circles-within-circles (epicycles on deferents) around the sun.
    5. elliptical orbits around the sun.

19. How is the sun situated in the universe?
    1. (*) The sun is just one of a large number of stars, located in the fringes of the Milky Way galaxy, which itself is just one of many galaxies.
    2. The sun is at the center of the universe.
    3. Earth is at the center of the universe, and the sun orbits around the earth.
    4. The sun is just one of the many stars clustered near the center of the universe.
    5. The sun is a one-of-a-kind and isolated star that is far outside of all the galaxies in the universe.

20. According to the planetary model, an atom is
    1. a single tiny object without any internal structure, not made of parts.
    2. made of positively charged matter balls with electrons embedded in it.
    3. made of a cloud of protons and electrons.
    4. made of protons, electrons and ions.
    5. (*) made of a small, massive positively charged nucleus and negatively charged electrons which are rather far from the nucleus.

21. Individual atoms cannot be seen using visible light, even with the help of optical microscopes, because
    1. they don't really exist - they are just a convenient model of matter.
    2. they are so tightly packed that one cannot separate them from the other atoms.
    3. they are much smaller then the aperture (opening) of any microscope.
    4. (*) the wavelength of visible light is too long compared to the size of atoms.
    5. the wavelength of visible light is too short compared to the size of atoms.

22. What is the similarity between combustion (burning) and respiration?
    1. both reactions create oxygen;
    2. (*) both reactions involve oxidation and liberate energy;
    3. both reactions consume energy;
    4. both reactions use energy to convert carbon dioxide into hydrocarbon componds;
    5. there is no similarity - they are completely different processes;

23. Roughly how many different elements are there?
    1. 5
    2. 20
    3. (*) 100
    4. 1000
    5. too many to count.

24. How many atoms are there in a glucose molecule, ?
    1. 3
    2. 4
    3. (*) 24
    4. 48
    5. cannot be determined from the information provided.

25. The circumference of Earth is approximately
    1. 4000 km
    2. 6500 km
    3. 13000 km
    4. (*) 40000 km
    5. 65000 km

26. The main compounds created when hydrocarbon compounds burn are:
    1. 
    2. ammonia and water
    3. methanol and
    4. (*) water and carbon dioxide
    5. hydrogen and oxygen

27. Heating air in an expandable balloon will
    1. (*) lead to an increase in volume due to the higher speed of the molecules.
    2. increase the density, because of the higher pressure.
    3. decrease the pressure since hot air is thinner (less dense).
    4. increase the pressure since heat equals pressure.
    5. not have any influence on the density of the air.

28. The diameter of the Sun is about 109 times that of Earth. How much bigger is the Sun's volume than that of Earth?
    1. 109 times
    2. 1090 times
    3. 12000 times
    4. 157000 times
    5. (*) 1.3 million times

29. The distance from Earth to the Moon is about 384 000 kilometers. How much is this in meters?
    1. 
    2. 
    3. (*)
    4. 
    5. 

30. One centimeter is closest to
    1. meters
    2. meters
    3. (*) meters
    4. 0.5 inches
    5. 2.54 inches

31. Which entity in the following list is the most massive (the heaviest)?
    1. water molecule
    2. oxygen atom
    3. hydrogen atom
    4. electron
    5. (*) alcohol molecule

32. According to the periodic table of the elements, elements are expected to have similar chemical properties if they
    1. (*) are in the same column (``group'') of the periodic table.
    2. are in the same row of the periodic table.
    3. have a similar number of electrons.
    4. have about the same weight.
    5. have a nucleus of about the same size.