Chapter 39: Q 6 Exercise (page 1136)

In one experiment, 6000 photons are detected in a O.10-mm- wide strip where the amplitude of the electromagnetic wave is 200 V/m. What is the wave amplitude at a nearby 0.20-mm-wide strip where 3000 photons are detected?

Short Answer

Expert verified

Hence, the wave amplitude at 0.20mm wide strip is100V/m

Step by step solution

01

Given information

In one experiment, 6000 photons are detected in a O.10-mm- wide strip where the amplitude of the electromagnetic wave is 200 V/m.

02

Explanation

The first strip's photon count is given by

N1=HI1δx1hf(1)

Count for second strip is:

role="math" localid="1648587585729" N2=HI2δx2hf(2)

Dividing (1) by (2):

N1N2=HI1δx1HI2δx2=I1δx1I2δx2

03

Calculations 

We have the values as:

N1=6000,n2=3000,I1=2002,I2=?,δx1=0.1mmandδx2=0.2mm

Substituting the values,

60003000=2002×0.1I2×0.2I2=100V/m

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Most popular questions from this chapter

What is the minimum uncertainty in position, in nm, of an electron whose velocity is known to be between 3.48×105m/sand 3.58×105m/s?

FIGURE Q39.1 shows the probability density for photons to be detected on thex-axis.

a. Is a photon more likely to be detected at x=0mor at x=1m ? Explain.

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FIGURE P39.32 shows |ψ(x)|2for the electrons in an experiment.

a. Is the electron wave function normalized? Explain.

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FIGURE P39.32 shows |ψ(x)|2for the electrons in an experiment.

a. Is the electron wave function normalized? Explain.

b. Draw a graph of ψ(x)over this same interval. Provide a numerical scale on both axes. (There may be more than one acceptable answer.)

c. What is the probability that an electron will be detected in a 0.0010-cm-wide region atx=0.00cm? At x=0.50cm? At x=0.999cm?

d. If 104electrons are detected, how many are expected to land in the interval -0.30cmx0.30cm?

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