Optics B/C

[cngu23]

If it's moving away, then the wavelength will increase therefore it's a red shift. If it's moving closer, then the wavelength will decrease meaning it will be a blue shift.

For calculation, what is the unit measure of z in the redshift formula?

[AlphaTauri]

If it's moving away, then the wavelength will increase therefore it's a red shift. If it's moving closer, then the wavelength will decrease meaning it will be a blue shift.

For calculation, what is the unit measure of z in the redshift formula?

z has no unit - it's just a dimensionless number.

[JSGandora]

Instead of using that, which doesn't help at all in this case, use the Relativistic Doppler Shift equation which is this:
http://hyperphysics.phy-astr.gsu.edu/hb ... ldop2.html

[cngu23]

Instead of using that, which doesn't help at all in this case, use the Relativistic Doppler Shift equation which is this:
http://hyperphysics.phy-astr.gsu.edu/hb ... ldop2.html

So if I use this equation instead of the one of doppler effect, for my previous problem, what would I use for v?

And there may be an error in the answer key for my previous problem. If an object is traveling away from the observer, I believe that the observed frequency would be less than the actually frequency, but the answer says that it increases by a factor of 10.
Can someone verify this?

Camas Division B test in test exchange.

[JSGandora]

Yes, the frequency should decrease. I think I took that test before and my answer disagreed with the answer key.

[Infinity Flat]

Yes, the frequency should decrease. I think I took that test before and my answer disagreed with the answer key.

My mistake, I used the Doppler Effect calculator linked above, and I may or may not have solved in the wrong direction.

[cngu23]

Yes, the frequency should decrease. I think I took that test before and my answer disagreed with the answer key.

Alright. So should the correct answer be 2.56 x 10^6? I used the doppler effect equation.

[Infinity Flat]

Yes, the frequency should decrease. I think I took that test before and my answer disagreed with the answer key.

Alright. So should the correct answer be 2.56 x 10^6? I used the doppler effect equation.

Using this calculator for relativistic Doppler effect, I get 8.00 * 10^5 Hz.

[JSGandora]

Sooo confusing @.@

So plugging the numbers in and using Wolfram Alpha, I get 1.25*10^6:

http://www.wolframalpha.com/input/?i=5s ... %29*10%5E6

[cngu23]

Sooo confusing @.@

So plugging the numbers in and using Wolfram Alpha, I get 1.25*10^6:

http://www.wolframalpha.com/input/?i=5s ... %29*10%5E6

My bad. I was using the wrong doppler effect equation. The one for sound.

for your wolframalpha calculation, you used 2.6461 instead of 2.8481. And also, v should be the velocity of the wave, not frequency. But since they are directly related, should that not matter?

EDIT: Actually, I used a calculator to verify your wolfram alpha calculation with 2.8481 instead of 2.6461. It turned out to be 8 x 10^5