Physics 251 Spring 1999
Modern Physics
Homework Assignment # 3, Due (in class) Monday February 8

Reading Assignment: You should finish Krane, Chapter 3, and start Chapter 4, this week, reading ahead of the lectures. By the middle of next week, the lectures will start Chapter 5. Problem Assignment: Provide a concise and readable derivation as well as a numerical answer. Part credit is given for sensible work even if the final answers are not right. The same will be true on exams.

1.

Krane, Chapter 3, p.95, #1.

2.

Krane, Chapter 3, p.95, #2.

3.

Krane, Chapter 3, p.95, #5.

4.

Krane, Chapter 3, p.96, #6.

5.

Krane, Chapter 3, p.96, #7.
[b.] Also find the power in Watts striking the sheet of paper, assuming that the light bulb radiates in all directions.
[c.] According to Eq.(3.10), the power $P=IA=E_0^2 A/2\mu_0 c.$ What is the average $\vec{E}$-field E₀ of the light from the bulb at this distance?

6.

Krane, Chapter 3, p.96, #9.

7.

Krane, Chapter 3, p.96, #20.