Answer:
agree with student 2, disagree with student 1
Explanation:
If you want to know if the wavelength of light was shifted you have to know the original wavelengths
Since we know the absorption spectrum for elements like hydrogen, we can look for these absorption lines in the star's spectra and figure out what direction these lines are shifted and tell if the star is moving away or towards us
The color of the star refers to the temperature of the star's surface which is not related to the doppler shift of the star
Answer:

Explanation:
Given that
Length = L
At initial over hanging length = Xo
Lets take the length =X after time t
The velocity of length will become V
Now by energy conservation

So

We know that



At t= 0 ,X=Xo
So we can say that

So the length of cable after time t

To protect a material from the influence of an external magnetic field, the material should be kept in soft iron ring.
So the correct answer is A.
Hope this helps,
Davinia.
Hmm, I got that the wavelength is 500 meters.
Answer:the human retina can only detect incident light that falls in waves 400 to 720 nano-meters long so we cant see microwave or ultraviolet wavelengths. this also applies to infrared lights which has wavelengths longer than visible and shorter than microwaves thus being invisible to the human eye
Explanation: