Sci 1120 Spring 2008 Review questions and problems for Exam 4

Chapter 20 review questions

Questions for Thought

  1. When did the first observations of magnetism occur?
  2. What did Niccolo Cabeo discover?
  3. What is meant by the fluid theory of electricity?
  4. What discoveries did Benjamin Franklin make in the electricity?
  5. Why is Gilbert called the “Father of Magnetism”?
  6. How did Du Fay show that there are two different types of charges?
  7. When as the electron discovered by whom?
  8. What is the charge of the electron? The proton? The neutron?
  9. What is a Leyden Cell? What was it used for?
  10. What are the three methods for charging an object?
  11. What is the difference between an insulator and a conductor?
  12. What is the principle of a Van de Graff generator?
  13. How does the force of electricity compare to the force of gravity?
  14. Why is gravity the dominant force in the universe and not electricity?
  15. How did Volta discover the principle to invent the battery?
  16. What is relationship between R, V, and I?
  17. What is Ohm’s law?
  18. What is the difference between series and parallel circuits?
  19. Why are households wired in parallel and not series?
  20. What is the difference AC and DC current?
  21. How does increasing the number of resistors connected in series affect the total resistance?
  22. How does increasing the number of resistors connected in parallel affect the total resistance?
  23. What was the battle between Thomas Edison and George Westinghouse?
  24. What does the product of the voltage (V) and the current (I) mean?
  25. What is the principle of a transformer? Do they work with AC or DC currents?
  26. Why do transmission power lines operate at 250,000 Volts or higher?
  27. Why is a Van de Graff generator not very dangerous while a household outlet can be deadly?
  28. What is the relation between electrical power and energy? What is it you pay for each month?
  29. What is the principle of a compass?
  30. What is meant by magnetic declination?
  31. Does the magnetic north pole ever change position?
  32. What is the evidence for the reversals in the Earth’s magnetic field?
  33. Who discovered that the Earth is a large magnet?
  34. What is the difference in the field produced by a single charge and dipole charge?
  35. What is the difference between a permanent magnet and an electromagnet?
  36. What is a ferromagnetic material?
  37. What does inserting an iron nail into a solenoid do the strength of the electromagnetic field?
  38. What does a moving electron experience in a magnetic field?
  39. What was one of the major accomplishments of Michael Faraday?
  40. What is the principle of magnetic induction?
  41. How does a metal detector operate?
  42. What scientific evidence is there supporting most magnetic healing devices on the market?
  43. What is a perpetual motion machine? Does one actually exist?
  44. What is meant by a double blind experiment?
  45. What is the principle of the MRI?
  46. What are two methods that animals use to navigate on the Earth?

 

Problems for Review

1. In a battery circuit with resistors in parallel, the

      a. voltage is different across each resistor.

      b. current through each resistor is the same.

      c. total resistance is smaller than the value of the smallest resistor.

      d. Both a and b are true

 

2. In a battery circuit with resistors in series, the

      a. voltage is the different across each resistor.

      b. current through each resistor is the same.

      c. total resistance is smaller than the value of the smallest resistor.

      d. Both a and b are true

 

3. In a battery circuit with resistors in series, the

      a. total resistance is equal to the value of the largest resistor.

      b. total resistance is smaller than the value of the largest resistor.

      c. total resistance is the sum of the individual resistors.

      d. total resistance is the same as the value of the smallest resistor.

 

Questions 4 and 5: A 15-V battery circuit is connected in series with three 5 ohm resistors.

4. What is the overall resistance?

a. 0.60 ohms

b. 1.67 ohms

c.  5 ohms

d.  15 ohms

e. 125 ohms

 

5. What is the overall current in the circuit?

a. 0.1 Amps

b. 0.2 Amps

c. 1.0 Amps

d. 5.0 Amps

e. 25 Amps

6. Which one of the following would be the safest?

a. a power supply at 5 volts

b. a power supply of 120 volts

c. a power supply with a current of 1.0 amp at 240,000 volts

d. a 120 volt source with unlimited current potential

 

7. What is the cost of running a 1 kW appliance constantly for 1 day? (Use 10 cents/kWh)

     a   2.4 cents

     b.  24 cents

     c. $2.40

     d. $24.00

 

8. Two equal positive charges are placed equidistant on either side of a negative charge, the negative charge would experience

a. a force to the left

b. a force to the right

c. a net zero force

d. a dipole force  

 

 

 

9. Magnetism results from

      a. the rotation of the Earth.

      b. the movement of magnetic monopole charges.

      c. stationary magnetic charges.

      d. the movement of electric charges.     

 

10.  A Van de Graaf generator produces a voltage of approximately

a. 10 volts

b. 120 volts

c.  150 volts

d. 240 volts

e. 30,000 volts  

 

11. Who developed AC power generation?

   a. Thomas Edison

   b. Benjamin Franklin

   c. Ernest Rutherford

   d. George Westinghouse

   e. Neils Bohr

 

12.  A current of 5.0 amperes flows through a resistance of 5 ohms. How much power is dissipated?

a. 2.5 Watts

b. 10 Watts

c. 20 Watts

d. 50 Watts

e. 125 Watts

 

Questions 13 and 14. An experiment is conducted to test the effect a magnetic bracelet on healing a muscle injury.  10 participants wear a bracelet containing magnetite while 10 other participants wear a bracelet containing only copper. 

 

13. Which one of the following would be an example of the placebo effect?

  a. Both groups reported no improvement in the healing process.

  b. Only the group with the magnetite reported significant improvement.

  c. Both groups reported significant improvement.

  d. The group with only copper know that they are wearing a bracelet without magnetite.

 

14. Which one of the following might would indicate the bracelet is effective in healing a muscle injury?

  a. Both groups reported no improvement in the healing process.

  b. Only the group with the magnetite reported significant improvement.

  c. Both groups reported significant improvement.

  d. The group with only copper know that they are wearing a bracelet without magnetite.

 

Questions 15 and 16: A 10-V battery circuit is connected in parallel with a 30, 30, and 30 ohm resistors.

15. What is the overall resistance?

a.   0.03 ohms

b.   0.1 ohms

c.    10 ohms

d.    30 ohms

 e.    90 amps

 

16. What is the overall current in the circuit?

a. 0.1 Amps

b. 0.3 Amps

c. 1.0 Amps

d. 9.0 Amps

e. 30 Amps

 

17. If the voltage across a resistor is doubled, the resistance will

      a. be doubled.

      b. be quadrupled.

      c. be cut in half.

      d. be cut to one-fourth.

 

 18. Which one of the following is a ferromagnetic material?

      a. Hydrogen

      b. Carbon.

      c. Cobalt.

      d. Helium.

 

19. What is the approximate declination angle for Bemidji?

a. 0 deg.

b. 3 deg.

c. 30 deg.

d. 45 deg.

e. 90 deg.

 

20. One ampere is a unit of

      a. power.

      b. voltage.

      c. electrical energy.

      d. resistance.

      e. current.

 

21. For a circuit, the current is

      a. proportional to resistance.

      b. inversely proportional to voltage.

      c. proportional to voltage.

      d. proportional to the square of the resistance.

 

22. For a simple circuit with a resistance of R = 10 ohms and voltage 10 volts, the current is I = 1 amp. If the voltage is increased to 20 volts what will be the values for R and I?

      a. R = 10 ohms I = 2 amps.

      b. R = 5 ohms I = 2 amps.

      c. R = 10 ohms I = 1 amp.

      d. R = 5 ohms I = 1 amp.

  

23. Plastic is an example of a(n)

      a. conductor.

      b. semiconductor.

      c. insulator.

      d. ohmic semiconductor.

 

24. A wire of 100 ohms and 1 amp of current generates 100 W of Joule heat loss. If the current is increased to 10 amps the heat loss will be

      a. 10 W

      b. 100 W

      c. 110 W

      d. 200 W

      e. 10,000 W

 

25. In a(n) ______________ electrons can move freely.

a. magnetic field

b. conductor

c. insulator

d. generator

 

 26. A resistor of 10 ohms is wired in series and to a 10-V battery. How much current flows in the circuit?

a. 0.01 amps

b. 1 amp

c. 10 amps

d. 100 amps

e. 1000 amps  

 

27. What is the cost of running a 1 kW appliance constantly for 30 days? (Use 10 cents/kWh)

a. 7.2 cents

b .$0.72

c. $7.20

d. $72.00

e. $720.00

 

28. The magnetic field lines around a current-carrying wire

      a. form closed loops around the wire.

      b. stretch radially from the wire in all directions.

      c. are always zero.

      d. are parallel to the direction of current in the wire.

 

29. Magnetic fields can deflect which one of the following?

a. a moving neutron

b. a moving proton

c. a stationary electron

d. a stationary proton

 

30. A toaster operating on 120 volts has a wattage rating of 1200 watts. What is the current flowing in the toaster?

a. 0.1 A

b. 1.0 A

c. 10 A

d. 120 A

e. 1200 A

 

31. A transformer with 1 turn on the primary coil is used to increase the voltage from 120 volts to 12,000 volts for a power line. How many turns should be in the secondary coil?

a. 1 turn

b. 100 turns

c. 120 turns

d. 1200 turns

e. 10,000 turns

 

32. An object has a million more protons than electrons.  What is the net charge on the object?

a. 1.6 x 10-13 C

b. 1.6 x 1013 C

c.  8 x 10-19 C

d.  1.6 x 103 C

e.  1.6 x 1019 C

             

33. An ac voltage can be easily increased or decreased using a

      a. generator.

      b. motor.

      c. transformer.

      d. fuse.

      e. battery.

 

34. What would happen if electrical power were transmitted from a generating station at 120 Volts?

a. The cost of electricity would be cheaper.

b. All the power would be lost to joule heating

c. The cost of electricity would remain the same

d. All the power would be converted to electrical energy more efficiently 

 

35. The unit for charge is the

      a. ohm.

      b. ampere.

      c. volt.

      d. coulomb.

 

36. Two resistors, 2 and 2 ohms, are wired in parallel and connected to a 10-V battery. What is the resistance of the circuit?

a. 0.2 ohms

b.  1 ohm

c.   4 ohms

d. 20 ohms

e.  40 ohms  

 

37. If the voltage across a resistor is doubled, the current will

      a. be doubled.

      b. be quadrupled.

      c. be cut in half.

      d. be cut to one-fourth.

      e. remain the same.

 

 

Chapter 21 review questions

Questions for Thought

 

  1. What were the basic models of the atom during the time of the Greeks?
  2. How did John Dalton show that elements were composed of individual atoms?
  3. Who proved the existence of electrons?
  4. How was the modern concept of the atom developed? How does the overall size of the atom compare to the size of the nucleus?
  5. What is the difference between a continuous spectrum and line spectrum?
  6. How are elements identified in the Sun from so far away?
  7. What is the Bohr model of the atom?
  8. What are the Balmer, Lyman, and Paschen series?
  9. What are isotopes and how are different isotopes of an element separated?
  10. When and how was radioactivity first discovered?
  11.  What are the different types of radiation?
  12. What is meant by half life and how does it vary among different types of elements?
  13. What is carbon 14 dating? Where does the C-14 come from?
  14. What is the difference between radioactive decay and fission?
  15. What was the Manhatten project and what was the most difficult part of the project?
  16. Where are the various nuclear reactors located around the country?
  17. What are the advantages and disadvantages of nuclear energy?
  18. What is Yucca Mountain and what is its purpose?
  19. What is the difference between fission and fusion to produce energy?
  20. What was the controversy over cold fusion?
  21. What are some of the biological effects of radiation?
  22. What is radon and why is it a concern for people in their homes?
  23. What were x-ray shoe fitting machines?

 

Problems for review

1. How many neutrons are there in an atom of 15N7?

 a. 1

 b. 7

 c. 8

 d. 15

 

 2. The atomic number ( Z ) of an element is equal to the number of_____ in one of its atoms.

 a. protons

 b. neutrons

 c. protons plus neutrons

 d. neutrons plus electrons

 

 3. The mass number ( A ) of a nuclide is equal to the number of________ in one of its nuclei.

protons

neutrons

protons plus neutrons

protons plus electrons

neutrons minus electrons

 

4. An element with an atomic number of 12 can be said to

a. be the sixth element discovered.

b. have six protons and six neutrons.

c. have six protons.

d. have eight electrons in its outer shell.

e. have twelve protons.

 

5. An element with a mass number of 12 can have

a. twelve electrons.

b. six protons and six neutrons.

c. six protons and six, seven, or eight neutrons.

d. twelve electrons in its outer shell.

e. twelve protons and twelve electrons.

 

6. Which of the following kinds of particles are made from quarks?

a. molecules

b. gravitons

c. electrons

d. protons

e. photons

 

7. The various isotopes of an element all have

 a. the same number of neutrons and the same number of protons.

 b. the same number of neutrons but different numbers of protons.

 c. the same number of protons but different numbers of neutrons.

 d. the same total number of neutrons and protons.

 

8. The first self-sustaining nuclear fission reaction was achieved in Chicago in 1942 under the direction of a scientist named:

Enrico Fermi

Albert Einstein

Isaac Newton

John Dalton

 

9. Which one of the following elements could possible undergo fission to produce energy?

   a. Hydrogen

   b. Oxygen

   c. Helium

   d. Radon

   e. Neon

 

10. Thermonuclear warheads, or hydrogen bombs, are based on the

 a. fission process of uranium to produce hydrogen.

 b. absorption of neutrons by uranium.

 c. emission of protons by uranium.

 d. fusion process for hydrogen.

 

11. What is the source of Radon in basements?

  a. Volcanic gases that leach into the ground.

  b. Radioactive decay of Hydrogen

  c. Radioactive decay of Uranium

  d. A chemical reaction of C-12 with Iron

  e. A chemical reaction of C-14 with Zinc

 

12. After three half-lives have elapsed, what fraction of the original amount of radionuclide remains?

 a. 1/3

 b. 1/4

 c. 1/8

 d. 1/32

 

13. The half-life of Co is 5.3 y. A sample is found to contain only 25% of the original amount of Co. How old is the sample?

 a. 5.3 y

 b. 11 y

 c. 16 y

 d. 21 y

14. The half-life of Sr is 30 y. What fraction of a sample of Sr will remain after 90 y have elapsed?

 a. 1/16

 b. 1/4

 c. 1/8

 d. 1/2

 

15. Compared to its matter twin, antimatter

a. has the same electrical charge.

b. has the same mass and electrical charge.

c. has the same mass and electrical charge, but opposite gravitational characteristics.

d. has the same mass, but opposite electrical charge and gravitational characteristics.

e. has the same mass and gravitational characteristics, but opposite electrical charge.

 

16. Which two forces have infinite range?

a. strong and weak

b. electromagnetic and strong

c. weak and gravity

d. gravity and electromagnetic

e. strong and gravity

 

17. How many protons are there in an atom of 35Cl17?

   a. 35

   b. 52

   c. 18

   d. 17

 

18. Which of these types of radiation has the greatest ability to penetrate matter?

 a. Alpha particles

 b. Beta particles

 c. Gamma rays

 d. Protons

 

19. If a mastodon bone has 25% the 14C/12C ratio of modern living matter, the bone is about how old?

(Half-life of C = 5730 y.)

 a. 1400 y

 b. 23,000 y

 c. 5700 y

 d. 11,000 y

 e. 57,000 y

 

20. Which group below shows the atomic building blocks in order of their size, largest to smallest?

a. molecule, atom, neutron, quark, proton

b. atom, neutron, quark, proton, electron

c. neutron, nucleus, proton, quark, electron

d. quark, neutron, proton, atom, molecule

e. molecule, atom, nucleus, neutron, quark

 

 

21. Which of the following is not a particle accelerator?

a. ring accelerator

b. cyclotron

c. synchrotron

d. linear accelerator

e. photon.

 

22. The amount of possible nuclear energy that is estimated to be contained in a telephone book would

a. equal ten dump-truck loads of coal.

b. be the same as ten hours of hydroelectric energy output of Niagara Falls.

c. run your motorcycle around the block.

d. provide electrical energy for the entire state of Minnesota for a year or more.

 

23. What is the energy source for a Fuel Cell?

a. Oxygen

b. Carbon Dioxide

c. Natural Gas

d. Hydrogen

 

24. Which of the following is true about radioactive decay?

a. It depends on chemical reactions.

b. Alpha decay results in one less neutron and one more proton.

c. It occurs much faster than nuclear fission.

d. It can convert tiny amounts of mass into energy.

 

25. Which of the following is true about radioactive decay of Uranium as compared to a fission reaction?

a. It occurs at a much slower rate compared to nuclear fission.

b. Alpha decay results in one less neutron and one more proton.

c. It occurs at a much faster rate than nuclear fission.

d. It is almost exactly the same process as nuclear fusion.

 

26. Which one of the following is the most likely candidate for carbon dating?

 a. A limestone rock about 5 million years old

 b. A bison bone about 6000 years old

 c. Charcoal from a fire about 500,000 years old

 d. A chip from a living tree about 500 years old

 

27. Cosmic rays hitting Earth's atmosphere lead to the formation of

 a. O-16.

 b. U-235.

 c. Pu-245

 d. N-14

 e. C-14

 

28. During the process of fission a U-235 atom takes how long on average to split?

 a. 700,000,000 years

 b. 4,200,000,000 years

 c. 200 days

 d. 3 hours

 e. 1 billionth of a sec

 

 29. The minimum amount of U-235 necessary to sustain a fission chain reaction is about

 a. 100 atoms.

 b. 100,000,000 atoms.

 c. 3 mg.

 d. 0.3 g.

 e. 2 kg.

 

 30. In nuclear fusion,

 a. an initial reaction triggers a chain reaction.

 b. light nuclei combine to form a heavier nucleus.

 c. a large nucleus splits into two smaller ones.

 d. protons are converted into neutrons and energy.

 

 31. The diameter of an average atom is about _________ times larger than an average nucleus.

 a. 0.0001

 b. 0.1

 c. 10

 d. 100,000

 e. 1,000,000,000

 

 32. What device is used to separate U235 and U-238?

 a. mass spectrometer.

 b. Geiger counter.

 c. a fluorine chemical reaction in an acid bath.

 d. a chemical reaction with Sodium Hydroxide.

 e. a linear accelerator.

 

33. The nucleus makes up about what percentage of the mass of an atom?

 a. 5%

 b. 10%

 c. 50%

 d. 99.9%

 

34. Which one of the following is expected to cause the least amount days of lost life?

a. Smoking 2 packs per day for 30 years

b. Smoking 1 pack per day for 30 years                                           

c.. Manufacturing work                                       

d. Radiation - 340 mrem/yr for 30 years                                               

e. Agriculture work

 

35.  Short-term and long-term effects of radiation on the health of the recipient are called ___ effects.

 a. somatic

 b. threshold

 c. genetic

 d. latent

 

36. Defects in the subsequent offspring of the recipient of radiation are called ____ effects.

 a. somatic

 b. threshold

 c. genetic

 d. latent

 

37. An electron is emitted by an atomic nucleus in the process called___________ decay.

Alpha

Beta

Gamma

Photon

 

38. The age of the Shroud of Turin was determined in 1988 using the process called ___________.

a. Carbon-14 dating

b. Biblical Records

c. Mass Spectrometry dating

d. Neutron scattering dating

 

39. What is an end product of matter-antimatter annihilation?

a. destruction of the universe

b. 100% energy

c. waste heat

d. di-lithium crystal

e. nuclear fission

 

40. When did the accident at Three Mile Island occur?

  a. 1942

  b. 1945

  c. 1954

  d. 1979

  e. 1986