Some Constants:
h = 6.63 x 10-34 J-s = 4.136 x 10-15 eV/Hz knowledge = power
mp = 1.673 x 10-27 kg me = 9.11 x 10-31 kg mn = 1.675 x 10-27 kg
Questions
1. Iodine-131, a beta emitter, has a half-life of 8 days. A 2-gram sample of initially pure iodine-131 is stored for 32 days. How much iodine-131 remains in the sample?
2. Two coils are arranged in close proximity to one another. The first coil is connected to a Duracell battery. Explain what, if any, effect this has on the second coil. Use an electromagnetism principle to justify your answer.
3. An electron moves from the n=1 state to the n=3 state. Did the electron absorb energy or release energy during this transition? Explain how you know.
4. Looking into the night sky, you see one star that appears yellow and another that appears red. Which star is emitting photons with the higher energy?
5. How many protons are inside the nucleus of an Ag-108 atom?
6. Iodine-131, a beta emitter, has a half-life of 8 days. A 3-gram sample of initially pure iodine-131 is stored for 16 days. How much iodine-131 remains in the sample?
7. An electron moves from the n=4 state to the n=3 state. Did the electron absorb energy or release energy during this transition? Explain how you know.
8. Looking into the night sky, you see one star that appears yellow and another that appears red. Which star is emitting photons with the higher speed?
9. How many protons are inside the nucleus of an He-8 atom?
Problems
1. A lamp emits its peak radiation at a wavelength of 8.8 x 10-5 m.
a. What type of EM wave is this?
b. Name something practical that this lamp may be used for.
c. What is the temperature of the bulb filament?
2. A hydrogen atom has its electron in the n=2 state.
a. How much energy must be absorbed for the atom to become ionized from this level?
b. What is the frequency of the photon that can supply this energy?
c. What type of EM wave is this?
3. What is the de Broglie wavelength of an electron traveling 100 m/s?
4. Pu-239 undergoes alpha decay. Write the reaction equation and the identity of the daughter nucleus.
5. A lamp emits its peak radiation at a wavelength of 2.1 x 10-7 m.
a. What type of EM wave is this?
b. Name something practical that this lamp may be used for.
c. What is the temperature of the bulb filament
6. A hydrogen atom has its electron in the n=3 state.
d. How much energy must be absorbed for the atom to become ionized from this level?
e. What is the frequency of the photon that can supply this energy?
f. What type of EM wave is this?
7. What is the de Broglie wavelength of an electron traveling 200 m/s?
8. N-15 and a proton fuse into a large nucleus plus an alpha particle. Write the reaction equation and determine the identity of the resulting nucleus.