Solution Found!

Physics / Physics with MasteringPhysics 4 / Chapter 30 / Problem 47P

Physics with MasteringPhysics | 4th Edition | ISBN: 9780321541635 | Authors: James S. Walker

Change Question

A laser produces a 7.50-mW beam of light, consisting of

Chapter 30, Problem 47P

(choose chapter or problem)

Get Unlimited Answers

QUESTION:

Problem 47P

A laser produces a 7.50-mW beam of light, consisting of photons with a wavelength of 632.8 nm. (a) How many photons are emitted by the laser each second? (b) The laser beam strikes a mirror at normal incidence and is reflected. What is the change in momentum of each reflected photon? Give the magnitude only, (c) What force does the laser beam exert on the mirror?

Questions & Answers

QUESTION:

Problem 47P

A laser produces a 7.50-mW beam of light, consisting of photons with a wavelength of 632.8 nm. (a) How many photons are emitted by the laser each second? (b) The laser beam strikes a mirror at normal incidence and is reflected. What is the change in momentum of each reflected photon? Give the magnitude only, (c) What force does the laser beam exert on the mirror?

ANSWER:

Step 1 of 3:

a)

Here, we have to calculate the number of photons emitted by the laser per second.

Given that,

$P=7.5\times{}1{0}^{3}\ watts$ .

$\lambda{}=632.8\ nm$ .

The energy of the laser beam is,

$E=nh\nu{}$

$P=\frac{E}{s}=\frac{nh\nu{}}{s}$

$\Rightarrow{}n/s=\frac{P}{h\nu{}}=\frac{P\lambda{}}{hc}$

$=\frac{7.5\times{}1{0}^{3}\times{}632.8\times{}1{0}^{-9}}{6.62\times{}1{0}^{-34}\times{}3\times{}1{0}^{8}}$

$=2.38\times{}1{0}^{22}$

So, per second the beam will emit $2.38\times{}1{0}^{22}$ number of photons.

Study Tools You Might Need

Chapter: 7 Problem: 12

Elementary Statistics 12
Problem 12BSC Finding Confidence Intervals. , Assume that each sample is a simple random sample obtained from a population with a normal distribution. Pulse Rates of Men and Women Data Set 1 in Appendix B includes 40 pulse rates of men, and those pulse rates have a mean of 67.3 beats per minute and

Chapter: Problem: 1

Myers' Psychology for AP 2
Heritability relates to the a. percentage of a persons intelligence that is due to environmental influences. b. percentage of a persons intelligence that is due to genetics. c. correlation of intelligence test scores among family members. d. extent to which variability among individuals intelligence

Chapter: Problem: 5.2

OpenIntro Statistics 3
The figure on the right shows three unimodal and symmetric curves: the standard normal (z) distribution, the \(t\)-distribution with 5 degrees of freedom, and the \(t\)-distribution with 1 degree of freedom. Determine which is which, and explain your reasoning.

Chapter: 2 Problem: 38

Holt Physics: Student Edition 2009 1
Two cars travel westward along a straight highway, one at a constant velocity of 85 km/h, and the other at a constant velocity of 115 km/h. a. Assuming that both cars start at the same point, how much sooner does the faster car arrive at a destination 16 km away? b. How far must the cars travel for t

Chapter: 18 Problem: 1

Biology: The Dynamic Science 5
What is a restriction fragment length polymorphism (RFLP)?

Chapter: 10 Problem: 8

Urban Economics 8
In a column of The State Paper (Columbia, South Carolina) on April 5, 2004, columnist John Monk describes the efforts of motorcycle riders to defeat a proposed law that would allow police to issue $25 tickets to automobile drivers and passengers who are not wearing seat belts. The law would not apply

Chapter: 7 Problem: 7

Urban Economics 8
Using Figure 177 as a starting point, suppose the initial utility-maximizing spending on special education is $5 rather than $25. As before, the lump-sum conditional grant for special education is $20. The income elasticity of demand for special education is 1.0. a. Show the response of the median ho

Chapter: 11 Problem: 9

Principles of Economics 9
Many transportation systems, such as the Washington, D.C., Metro (subway), charge higher fares during rush hours than during the rest of the day. Why might they do this?

Not The Solution You Need? Search for Your Answer Here:

×

Login

Login or Sign up for access to all of our study tools and educational content!

×

Register

Sign up for access to all content on our site!

Or login if you already have an account