Question

5) WILL GIVE MEDAL AND FAN!!

Which of the following can you say about a star with a greater shift in its spectrum than another star?

a. It is moving slower.

b. It is moving faster.

c. It is not moving at all.

d. It is exploding into a supernova.

Answer 1

@brae
If an object emitting light(like a star) is not moving relative to your position, then if you measure it spectrum at the beginning of the month and then again at the end of the month, there will be NO shift, since it's stationary relative to you.

If a star is moving towards you, it wavelengths of light appear compressed, just like the sound of a moving car speeding towards you gets louder, it's the doppler effect, and the star's spectrum gets blue shifted.

If a star is moving away from you, it's just like a police siren racing away from you as the sounds gets fainter and fainter, the light moving away from you gets red shifted.

Therefore, the faster something(like a star) moves either away from you or towards you, the greater the shift in its spectrum.

So in terms of the question, the greater the shift in a star's spectrum, the faster it's moving!

Does that make sense? :o)

Answer 2

oh s then it would be B? @SinginDaCalc2Blues

Answer 3

@Brae, are you really asking me if it's B?
I took the time to write my response in hopes that you understand the question.
You tell me what the answer is! :o)

Answer 4

not that good with science. sorry so if its not B then would it be D? so sorry @SinginDaCalc2Blues

Answer 5

you don't have to be sorry, and being good in science is easy, you just need to take the time to think about nature.
I'm willing to help you truly understand your questions but I would advise against just coming here to get answers. This is a great place to learn and there are alot of people here that can help.

I'm not going to tell you A, B,C, or D
The answer was very clearly written in my response.
If you want to discuss it, I am willing. :o)

Answer 6

thank you so much. yes I would like that. @SinginDaCalc2Blues

Answer 7

So first of all, is this an astronomy class?

Answer 8

its earth science. but we have started to work on the solar system @SinginDaCalc2Blues

Answer 9

Okay, well I have to ask the obvious question...did you read your chapter?

Answer 10

yes I did and I still didnt quite get it after reading it 2 times @SinginDaCalc2Blues

Answer 11

okay, well with that type of effort, I am more than willing to help you understand! :o)
What is confusing you the most about the spectrum?

Answer 12

You know that the spectrum of something(like a star) is simply the white light coming from the star and being sent through a prism and the white light is broken up into all the colors of the rainbow. With me so far?

Answer 13

yes! @SinginDaCalc2Blues

Answer 14

okay well light itself moves like a wave in water, it has a height from the bottom to top of the wave called the amplitude(but you can ignore that for now) and it has a wavelength and a frequency...

if you sit on the beach, really slow waves take longer to reach you and the length between each wave is longer and the reach you less frequently...faster waves reach you quicker with a higher frequency...

look at this pic http://images.tutorvista.com/cms/images/83/frequency-wavelength-image1.PNG

Answer 15

if a star is moving towards you, the wavelengths are squished up like an accordion...if the star is moving away from you, they are stretched out like the bottom pic...does all that make sense?

Answer 16

ok i got that ! :)

Answer 17

ok great! now...
look at this pic which is called a blueshift in a spectrum
http://moodleshare.org/pluginfile.php/5389/mod_page/content/1/blueshift.jpg

Answer 18

ok

Answer 19

do you see the spectrum on the left?

Answer 20

i think so

Answer 21

there are 2 pictures of a rainbow(spectrum)
I want you to look at the one on the left

Answer 22

do you see the little black lines?

Answer 23

ohh yes yes

Answer 24

ok good...now stay with me here, I only have a few minutes okay...
I want you to pretend you have a telescope and you point it at a star on April 1st at midnight but instead of using your eye, the light from the star goes through the scope, then through a prism, and you take a picture of the spectrum you see on the left...got it?

Answer 25

ok..

Answer 26

ok great...then 1 month later on May 1st at midnight, you do the same exact thing...the light goes through your scope, through a prism, into your camera, and you take the picture that you see on the right side...got it?

Answer 27

ok

Answer 28

do you see how those little black lines have ALL SHIFTED TOWARD THE BLUE?

Answer 29

all of them shifted away from the red portion of the rainbow towards the bluer portion

Answer 30

let me know when you see that

Answer 31

okok ya i see it

Answer 32

this is the really neat part...you were looking at the same star right?
But the spectrum looks different, even though it's the same star light.
Here is the reason:
It's because the star is moving towards you!

Answer 33

Remember how a police car get louder as it races towards you?

Answer 34

yes! :)

Answer 35

it's the same thing!
All those silly little sound waves are getting squished up...so is the light from the star...it's getting squished up too because it's moving towards you! Do you get that?

Answer 36

yes!!

Answer 37

okay great! now I want you to think about this question okay!

Answer 38

if you had 2 police cars racing at you, car A is going 50 mph and car B is going 100mph...if you use your imagination and pretend to "see" the sound waves coming towards you, which sound waves would be more squished up and reaching you faster?

Answer 39

car B because its comming at a faster paste

Answer 40

yup! good job! now...think here...

Answer 41

remember the two pictures of the star and the little black lines?

Answer 42

i want you to use your imagination again and imagine a 3rd spectrum, where the black lines are shifted even further down than the picture on the right...can you see it in your mind?

Answer 43

the new picture has its black lines shifted even further towards the blue...can you picture that?

Answer 44

yup

Answer 45

okay, well if the 3rd spectrum is shifted even more towards the blue, that means its wavelengths are even more squished up than the 2nd picture ...does that make sense?

Answer 46

yes im starting to get it more

Answer 47

okay so here we go...I think you will get it now...

Answer 48

going back to your original question:
Which of the following can you say about a star with a greater shift in its spectrum than another star?

Answer 49

if the 3rd picture of the spectrum in your imagination has been shifted more than the 2nd picture, which picture has its wavelengths more squished up?

Answer 50

wait so are you saying that the 3rd picture has been shifted more then the 2nd one? because that would be the 3rd pic right?

Answer 51

yup! :o)

Answer 52

...and the police car that was moving towards you faster had sound waves more squished up than the slower car right?

Answer 53

yay

Answer 54

so try and answer your question now that you are an "EXPERT!" :O)

Which of the following can you say about a star with a greater shift in its spectrum than another star?

a. It is moving slower.

b. It is moving faster.

c. It is not moving at all.

d. It is exploding into a supernova.

Answer 55

Come on @Brae!!! You can do it! Use those skills girlfriend! :o)

Answer 56

wouldnt it be moving slower?

Answer 57

since theres more in it?

Answer 58

remember the police car for reference...more squished up=faster car=more shift...same as starlight
if wavelengths are squished up, then they are reaching you faster...try again, but don't guess, use your imagination and "see it in your mind" you can do it! :o)

Answer 59

thanks! let me think

Answer 60

wait if there not going fast or slow. then would they not be moving at all?

Answer 61

that is true, if a star is not moving, there is no shift

Answer 62

omg so it is C

Answer 63

no

Answer 64

read the question
Which of the following can you say about a star with a greater shift in its spectrum than another star?

a. It is moving slower.

b. It is moving faster.

c. It is not moving at all.

d. It is exploding into a supernova.

Answer 65

I'm think you are still confused right?

Answer 66

well I thought it was B, but then I guess its not so that makes it D?

Answer 67

no...it's definitely not D...there is not enough information from a spectrum to tell is the star is exploding

Answer 68

The answer is actually B
But I hope you truly understand why

Answer 69

I dont know what it is because I think i tried all the answers so sorrrryy

Answer 70

ohh. ok! thank you so much for all the information!

Answer 71

and all the help!!!

Answer 72

If you would like I think I can draw a little picture of 3 stars that will make sense

Answer 73

its ok! Ill go over all the oics and things that u typed

Answer 74

pics**

Answer 75

make sure to read the very first thing I wrote..it's all in there...also go to youtube and find a video! :o) I wish you luck and also, don't get discouraged! Science is so powerful, don't be afraid, attack it and learn to love it! :o)

Answer 76

thanks so much!!! you are the best and im so thankful for you to help me!!

Answer 77

awww your welcome! :o)

Answer 78

Have a good night!

Answer 79

you too!! :)