BabyQuiz

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Baby-Quiz

• Where would you most likely find an electron in
  the first excited state for a one-dimensional
  box?
• Why do some minerals glow when they are
  illuminated with ultraviolet light?
• The wavelength of red light is 600 nm. An
  electron with a speed of 1.2 km/s has the same
  wavelength. Will the electron look red? Explain.
• An electron and proton have the same speeds.
  Which has the longer wavelength? Why?

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• What observation told scientists that nuclei had
  to contain more than just protons?
• What is a nucleon?

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• Which of the three types of radiation will
  interact with electric field?
• Why do beta rays and alpha rays deflect in
  opposite directions when moving through a
  magnetic field?

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Alpha Decay
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Transmutation
parent daughter
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Smoke Detectors
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Q-Value
The energy released is called the disintegration
energy, Q or Q-value
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Beta Decay
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Gamma Decay
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• What happens to the charge of the nucleus when it
  decays via beta plus decay?
• What happens to the charge of the nucleus when it
  decays via electron capture?
• What changes in the numbers of neutrons and
  protons occur when a nucleus is bombarded with a
  deuteron (containing one neutron and one proton)
  and an alpha particle is emitted?

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Half-Life and Rate of Decay
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The number of decays DN that occur in a very
short time interval Dt is proportional to Dt and
the total number N of radioactive nuclei present
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The number of decays per second is called the
activity of the sample.
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Units of Activity
1 Ci3.70x1010 decays per second
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The half life of an isotope is defined as the
time it takes for half the original amount of
isotope in a given sample to decay.
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• You place a chunk of radioactive material on a
  scale and find that it has a mass of 4 kilogram.
  The half-life of the material is 10 days. What
  will the scale read after 10 days?
• A radioactive material has a half-life of 50
  days. How long would you have to watch a
  particular nucleus before would see it decay?