PH221 - LAB - Assignment 5-8

6) A beam of light with red and blue components of wavelengths 670 nm and 425 nm,

respectively, strikes a slab of fused quartz at an incident angle of 30o. On refraction, the

different components are separated by an angle of 0.001312 rad. If the index of

refractions of the red light is 1.4925, what is the index of refraction of the blue light?

Week 5 Assignment

Early Quantum Theory

Please solve the following problems. You must show all work for full/partial credit.

When complete, attach a typed cover sheet and submit to the assignment drop-box.

1) The walls of a blackbody cavity are at a temperature of 27o C. What is the frequency

of the radiation of maximum intensity?

2) Assume that a 100 – W light bulb gives off 2.50% of its energy as visible light. How

many photons of visible light are given off in 1.00 min? (Use an average visible

wavelength of 550 nm)

3) What is the energy of photons (joules) emitted by an 107.5-MHz FM radio station?

4) What is the longest wavelength of light that will emit electrons from a metal whose

work function is 3.50 eV?

5) A metal with a work function of 2.40 eV is illuminated by a beam of monochromatic

light. If the stopping potential is 2.5V, what is the wavelength of the light?

6) What is the de Broglie wavelength of a 1000 kg car moving at a velocity of 25 m/s?

7) A hydrogen atom in its ground state is excited to the n = 5 level. It then makes a

transition directly to the n = 2 level before returning to the ground state.

a) What are the wavelengths of the emitted photons?

b) Would any of the emitted wavelengths be in the visible region?

8) What is the longest wavelength light capable of ionizing a hydrogen atom in the

ground state?

Week 6 Assignment

Quantum Mechanics of Atoms

Please solve the following problems. You must show all work for full/partial credit.

When complete, attach a typed cover sheet and submit to the assignment drop-box.

1) What is the minimum uncertainty in the velocity of an electron that is known to be

somewhere between 0.050 nm and 0.10 nm from a proton?

2) The energy of the first excited state of a hydrogen atom is -0.34 eV ± 0.0003 eV.

What is the average lifetime of for this state?

3) Knowing that a free neutron has a mean life of 900 s and a mass of m = 1.67 x 10-

27kg, what is the uncertainty in its mass in kg?

4) For n = 5, l = 4, what are the possible values of and ml and ms?

5) Draw the ground state energy level diagrams for nitrogen (N) and potassium (K).

6) Calculate the magnitude of the angular momentum of an electron in the n = 7, l= 5

state of hydrogen.

Week 7 Assignment

Nuclear Physics

Please solve the following problems. You must show all work for full/partial credit.

When complete, attach a typed cover sheet and submit to the assignment drop-box.

1) What is the approximate atomic radius of

2) What is the approximate radius of a nucleus?

(b) Approximately what is the value of A for a nucleus whose radius is 3.0 x 10-

15m?

3) Calculate the binding energy per nucleon for a nucleus.

4)

5) Polonium-214 can decay by alpha decay.

a) The product of its decay has how many fewer protons the polonium-214?

b) Write the nuclear equation for this decay.

6) Write the nuclear equation for the decay of ? If there are any alpha, beta or

gamma particles created what is their maximum kinetic energy created? Ignore recoil

energy of the nickel!

7) Francium-223 ( ) has a half-life of 21.8 min.

a) How many nuclei are initial present in a 25.0 mg sample?

b) How many nuclei are present 1h and 49 min later?

8) What is the activity of a sample of that contains 8.9 x 1022 nuclei?

Week 8 Assignment

W8 Assignment "Nuclear Reactions" Physics II

Nuclear Reactions

Please solve the following problems. You must show all work for full/partial credit.

When complete, attach a typed cover sheet and submit to the assignment drop-box.

NOTE: READ Week 8 announcement for information on threshold energy and formula.

1) Complete the follow nuclear reactions:

2) Consider the reaction

a) Use the masses of the nuclides involved to determine whether it is endogenic

or exoergic.

b) If it is exoergic, find the amount of energy released, if it is exoergic find the

threshold energy.

3) Find the threshold energy for the following reaction:

4) Find the threshold energy of the following reaction:

5) Calculate the energy released in the fission reaction: