# Search results

1. ### Nonlinear optics: second order polarization calculation

This is a problem from Boyd Nonlinear Optics chptr 1 problem 2. Homework Statement Numerical estimate of nonlinear optical quantities. A laser beam of frequency ω carrying 1 W of power is focused to a spot size of 30μm diameter in a crystal having a refractive index of n =2 and a second order...
2. ### Quantum Mechanics e-2, Bransden & Joachain

My intro QM class is currently using this text, but I find that there is not very many worked examples of problems, and there are no solutions for the chapter questions in the back. My class assignments are not based out of the book, so I was wondering if anyone knew of a solutions manual I...
3. ### Finding the coeffiecients of a sine series for -3*cos(8*pi*x/L)

I'm sorry if I came off as offended and defensive. I wasn't trying to. I did notice after that you had the same identity written down as tiny tim, but I had already posted twice and didn't want to go back and post again. I'll respond more carefully in the future so this doesn't happen again.
4. ### Finding the coeffiecients of a sine series for -3*cos(8*pi*x/L)

Worked perfectly! Thanks alot.
5. ### Finding the coeffiecients of a sine series for -3*cos(8*pi*x/L)

I am aware of the orthogonality relations, however I am not familiar with how they are derived, that is not covered in my textbook unfortunately. I do know that sin and cos are orthogonal on the interval -L to L, but they are not orthogonal on the interval 0 to L (according to my text), so this...
6. ### Finding the coeffiecients of a sine series for -3*cos(8*pi*x/L)

Homework Statement all i really need to do is solve the integral: \int-3*sin(\frac{n*pi*x}{L})*cos(\frac{8*pi*x}{L}) from x=0 to x=L Homework Equations The Attempt at a Solution I'm not very sure where to start with this. Any help would be appreciated.
7. ### An Exploration of Unified Theories

Sound waves are longitudinal and water waves are transverse. The median in which they propagate is matter. What you seem to be interested in is string theory(I noticed you changed your original post) I would suggest you read a book called the elegant universe by Brian Greene. Also What...
8. ### A 500 pound fly (this is not a HW question)

I'm not sure exactly what you mean could you elaborate I am curious now.
9. ### A 500 pound fly (this is not a HW question)

If the colum of air was the same, the bird would hover without falling.
10. ### A 500 pound fly (this is not a HW question)

The OP stated that he means the mass of the system, which means everything inside the plane. The Planes mass itself cannot change. I think the problem here is that people Aren't distinguishing between mass and weight. If you look at the system from the outside, the force required to hold up...
11. ### A 500 pound fly (this is not a HW question)

if you think about it in terms of Newtons law F=ma then it makes sense. to accelerate the entire system by, say, 20m/s^2 then the force required is F=(m-plane+m-people+m-fly +...)*20m/s^2.
12. ### A 500 pound fly (this is not a HW question)

First of all, you have to define "adding mass to the plane". If you mean does the fly add mass to the plane in terms of mass being accelerated: if the fly were hovering on take off, the fly would not add mass, but it would add weight, due to the air being pushed down by its wings to lift itself...
13. ### An Exploration of Unified Theories

question 1 There is definitely a correlation between colors and musical notes, as they are both waves. Light is an electromagnetic wave, which means it is oscillating electric and magnetic fields. Sound is a wave as well, although in this case a longitudinal wave, not a transverse wave like...
14. ### Earth's Magnetic Field vs Cell Phone EMF

The energy of the photons your body absorbs is still much less than that of the sun. You'll do more harm standing outside than using a Bluetooth headset.
15. ### Compressing air

ah i see. thank you for the correction, i seem to have missed the fact that there was obviously air being pushed into the flask.
16. ### Compressing air

i think if you had a 100PSI compressor, you could raise the pressure by 100PSI. the volume would remain the same, so T would go up by the same factor. 100PSI is 14 times atmospheric pressure, so the temperature would increase by a factor of 14. but i'm not 100% sure. hopefully someone else...
17. ### Simple Electric Field Problem

it might help if you draw electric field lines running from the positive to negative charge to help yourself visualize what is going on. if you don't know what electric field lines are there is a perfect example of how to draw electric field lines between a positive and negative charge...
18. ### Atwood's machine with a cylinder

Homework Statement a massless string of negligible thickness is wrapped around a uniform cylinder of mass m and raidus r. the string passes up over a massless pulley and is tied to a block of mass m at its other end. the system is released from rest. what are the accelerations of the block...
19. ### Fourier transforms

would i take the integral of each function squared and the square root of that?
20. ### Fourier transforms

okay i did know that, but i don't know how to find the root mean square of each waveform. the problem is in my lack of knowledge of statistics it seems...
21. ### Fourier transforms

Homework Statement 3. Consider the narrow triangular voltage pulse V(t) shown in the figure. i can't paste the function but its a piecewise function of the form: V(t)={1+(1/a)t from -a <=t<=0 {1-(1/a)t from 0<t<=a { 0 otherwise (a) Find and sketch the spectral content...
22. ### Impact Parameter

okay, i just figured it out, my brain must not have been working properly. sorry.
23. ### Impact Parameter

I'm in a second year physics course, and were studying Rutherford scattering. I'm not having any trouble with the physical or mathematical concepts, I'd just like a more precise definition of the phrase "impact parameter". I searched google, and my notes and textbook but couldn't really find...
24. ### Contribution of physics

i've heard people describe it as physics is the science behind engineering. if you look at it that way, which makes sense, because many of today's technological advances comes from the field of engineering without the study of physics our standard of living would not be the same without phyics.
25. ### Physics Careers involving physics?

i have been thinking about graduate school, but what sort of marks would i need to get into any graduate schools? from what i've heard its very competitive, but i would love to do that.
26. ### Distacne of planet

alright well since a microacrsec is 10^-6 arcsecs, and i said thousandths which would be 10^-3, i was pretty close. but thank you for the correction.
27. ### Speed when swinging from a rope?

really basic trig.
28. ### Distacne of planet

the triangulation method would be very inaccurate but they measure very small angles. for example, most astronomical measurments are done in arcseconds, where 1 arcsec = 0.000277777778 degrees. calculations in arcsec's are done to small numbers. from what i've seen in my limited astronomy...
29. ### Motion with Constant Acceleration (True/False)

dude don't worry at least you gave it alot more thought then some people would have. just remember with vector quantities like accelaration and displacement and velocity, direction matters.
30. ### Speed when swinging from a rope?

the angle has nothing to do with the energy, only in finding the height.