• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Physics Unit 4 JUNE 11/6/12

How well did you do on the exam?


  • Total voters
    5
Messages
225
Reaction score
56
Points
28
I dont think i've seen nething like this before :S
i'll nt solve it me neither i thnk its nt 4 our syllabus astrophysics is a bit confusing isn't it?like u kno the answers bt like smetimes i jst ans them and im nt fully understood the concept
 
Messages
2,951
Reaction score
17,783
Points
523
i'll nt solve it me neither i thnk its nt 4 our syllabus astrophysics is a bit confusing isn't it?like u kno the answers bt like smetimes i jst ans them and im nt fully understood the concept
Yeah i guess :p
N VERY true :| Even if u know it, u dunno how to explain it properly sumtymz :(
 
Messages
225
Reaction score
56
Points
28
Yeah i guess :p
N VERY true :| Even if u know it, u dunno how to explain it properly sumtymz :(
jst nw it happned wth me :) i wanna ask u the wavelength we receive frm a star i red shifted incomparsion 2 1 in the laboratory so the wavelength is the peak wavelength or no?
 
Messages
2,951
Reaction score
17,783
Points
523
jst nw it happned wth me :) i wanna ask u the wavelength we receive frm a star i red shifted incomparsion 2 1 in the laboratory so the wavelength is the peak wavelength or no?
It always keeps happening with me :oops:
I dint get u sorry :oops: What are u asking again?
 
Messages
225
Reaction score
56
Points
28
It always keeps happening with me :oops:
I dint get u sorry :oops: What are u asking again?
the wavelength we receive frm a galaxy is the peak wavelength always likein the redshift they show u a shift in a certain wavelength is tht the peak 1?.
 
Messages
2,951
Reaction score
17,783
Points
523
the wavelength we receive frm a galaxy is the peak wavelength always likein the redshift they show u a shift in a certain wavelength is tht the peak 1?.
We recieve a range of wavelengths from the galaxy acctually (remeber the bell-shaped curve for Wien's displacement Law?)
and its not nessecary that it's ALWAYS the peak one, all the wavelengths will show the same shift.
 
Messages
225
Reaction score
56
Points
28
We recieve a range of wavelengths from the galaxy acctually (remeber the bell-shaped curve for Wien's displacement Law?)
and its not nessecary that it's ALWAYS the peak one, all the wavelengths will show the same shift.
ahh ok and i shldn't confuse ths wth the previous parts as i always does
 
Messages
225
Reaction score
56
Points
28
well, usually the parts are related tho ;)
:) i don kno wat 2 say im really embarressed frm asking alot :( nw i answered 1 que and i found my ans wrng so can u explain it 2 me if tht's ok:) astrophysics as usual:) old papers Q88 last part abt speed calculation and Q87 and i repeat my apology:)
 
Messages
2,951
Reaction score
17,783
Points
523
:) i don kno wat 2 say im really embarressed frm asking alot :( nw i answered 1 que and i found my ans wrng so can u explain it 2 me if tht's ok:) astrophysics as usual:) old papers Q88 last part abt speed calculation and Q87 and i repeat my apology:)
Its perfectly okay with me :D Dont feel so, I'm learning a lot myself :)

Q87 I dunno what formula they are using :eek: I used a = v^2/r but I'm not getting the answer :S
@87 which part?

Dont apologize please :) I'm sorry for my late responses btw :oops:
 
Messages
225
Reaction score
56
Points
28
Its perfectly okay with me :D Dont feel so, I'm learning a lot myself :)

Q87 I dunno what formula they are using :eek: I used a = v^2/r but I'm not getting the answer :S
@87 which part?

Dont apologize please :) I'm sorry for my late responses btw :oops:
thnx :) all of it if u can :)
 
Messages
2,951
Reaction score
17,783
Points
523
thnx :) all of it if u can :)
Welcome n sure ...

Red Giants are stars with a large surface and cooler. They have moved off the main sequence.
Parallax displacement is the apparent change in angle of a star when viewed from the earth six months apart compared to a distant fixed star.

5 days (1 wave)

B is more luminous than A when viewed from earth. The maxima and minima are higher for B

Since luminosities are same, yet B appears brighter, A must be farther away from the earth to appear less brighter.

Contract: Gravitational forces
Expand: forces due to gas pressure and nuclear reaction
 
Messages
225
Reaction score
56
Points
28
Welcome n sure ...

Red Giants are stars with a large surface and cooler. They have moved off the main sequence.
Parallax displacement is the apparent change in angle of a star when viewed from the earth six months apart compared to a distant fixed star.

5 days (1 wave)

B is more luminous than A when viewed from earth. The maxima and minima are higher for B

Since luminosities are same, yet B appears brighter, A must be farther away from the earth to appear less brighter.

Contract: Gravitational forces
Expand: forces due to gas pressure and nuclear reaction
thnx :) bt y B is more luminous? and how distances can be diff?
 
Messages
2,951
Reaction score
17,783
Points
523
thnx :) bt y B is more luminous? and how distances can be diff?
No problem :D

B is as luminous as A according to the question, but from the earth it seems less brighter. That can only happen if B is far. LIke if u have something far it seems less bright than if it were near :)

How much are u done with? I'm doing Past papers now :)
 
Messages
225
Reaction score
56
Points
28
No problem :D

B is as luminous as A according to the question, but from the earth it seems less brighter. That can only happen if B is far. LIke if u have something far it seems less bright than if it were near :)

How much are u done with? I'm doing Past papers now :)
ok y b according 2 the graph is more luminous im also doin past papers bt i didn yet revise the bok:( and sme ques i solved b4 nw im nt able 2 solve and i started taking more time in solving ques than usual
 
Messages
2,951
Reaction score
17,783
Points
523
ok y b according 2 the graph is more luminous im also doin past papers bt i didn yet revise the bok:( and sme ques i solved b4 nw im nt able 2 solve and i started taking more time in solving ques than usual

It 'appears' more luminous but it isnt. Thats exactly what ís the reason for it being far away.



ahan! I did the Study Guide and now the papers... n i think its cuz of exam pressure... >.<" Its hard to do stuff when ur tensed n nervous :(
 
Messages
225
Reaction score
56
Points
28
It 'appears' more luminous but it isnt. Thats exactly what ís the reason for it being far away.



ahan! I did the Study Guide and now the papers... n i think its cuz of exam pressure... >.<" Its hard to do stuff when ur tensed n nervous :(
ya:( and smetimes u ned 2 thnk of an ans and the time is jst running away
 
Top