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vitaly

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1. Assume that sodium produces monochromatic light with a wavelength of 5.89x10^-7 m. At what rate would a 10 watt sodium vapor light be emitting photons?

A. 3.5x10^19 photons/s

B. 3.0x10^19 photons/s

C. 2.5x10^19 photons/s

D. 2.0x10^19 photons/s

I don't even know how to start this problem. We have never done anything with photons yet in our class. I tried looking for an equation, but I couldn't find anything. Does anybody know a certain equation I have to use to solve this?

2. Non-polarized light first passes through one polarizing filter and then through a second. If the intensity of light emerging from the second filter is 12.5% of hte light that struck the first filter, at what angle must the axes of the two filters be with respect to one another?

A. 7 degrees

B. 30 degrees

C. 42 degrees

D. 60 degrees

E. 83 degrees

Again, we have never covered polarization, but I think to find an angle you have to use inverse tangent. I just don't know what value to use the inverse tangent on. How can I solve this problem??

3. At transmission, diffraction grating is ruled with 5000 lines per cm. Through what angle will the first order maxima be deflected when light with a wavelength of 4.5x10^-7 m strikes the grating at an angle of incidence of 0 degrees?

Again, never had this material. But again, don't you use the inverse of a function to find the angle needed? But like in the last problem, I don't know what value to use the inverse on. Is there a formula I could use?

All help is appreciated. Thanks.