Physics Independent Trials 09' (2 Viewers)

[Macdwg]

yes because it was really generalised and required alot of thought.
I believe that honestly i got 0 in that part. even though i filled the page even with notes up the side.

 

[Macdwg]

abhi where did u lose marks btw?

 

[youngminii]

Ahaha my model of light was epic fail. I ended up talking about Einstein's Special Relativity, Hertz's radio wave experiment (also how it combined study of optics and EMR), and Michelson Morley's experiment.
But I forgot Hertz's name so I left a blank space wherever I was supposed to use it to fill in later (which I never did) LOL

Say, was the velocity time graph only talking about magnitude? 'cause my friend says his graph bounced back up

 

[abhi23]

abhi where did u lose marks btw?

i dont know yet, ive only got marks back not the paper.
But i'll post up when i get it back.
Do you know the multiple choice answer with the loops of wire in mag field B1 and B2?
i wasnt sure about that one

 

[shady145]

yeh there weren't too many calculation questions.
Did you have the 6 or 7 mark question about contributions to the theory of light that Bragg was refering to in a quote?
I thought that was probably the hardest one in the exam.

that was a 6 mark question which i got 6/6 ^^ easy. i talked about
maxwell
plank
de broglie
einstein.

my teacher commented that the only other thing i could have done was hertz but he said i had enough for the full marks.
when i get my exam back to keep i can post up my answer if u want???

 

[shady145]

Ahaha my model of light was epic fail. I ended up talking about Einstein's Special Relativity, Hertz's radio wave experiment (also how it combined study of optics and EMR), and Michelson Morley's experiment.
But I forgot Hertz's name so I left a blank space wherever I was supposed to use it to fill in later (which I never did) LOL

Say, was the velocity time graph only talking about magnitude? 'cause my friend says his graph bounced back up

yep i lost 1 mark there XD
didnt really notice the 'magnitude' part. so it went straight down left to right lol

 

[Macdwg]

i dont know yet, ive only got marks back not the paper.
But i'll post up when i get it back.
Do you know the multiple choice answer with the loops of wire in mag field B1 and B2?
i wasnt sure about that one

It was Into the Page and then Out of the page. That was because the arrows pointed in the direction of the electron that was flowing so you have to use the opposite direction.

I got my mark back. A little dissapointed, only got 70 but that included the option topic. I just seemed to bleed marks throughout certain parts. Including some calculations. I think that maybe it was marked a little hard but it's hard to tell.

 

[abhi23]

i meant the second one on which one was stronger
i just said B2 was stronger because it turned over a shorter distance

 

[untouchablecuz]

centripital force = magnetic force

i.e. mv^2/r = qvBsinx

r=mv^2/qvBsinx=mv/qBsinx

r is inversely propotional to B i.e. r oc 1/B

hence a greater radius means a weaker B field and vice versa

use this to answer the Q

 

[untouchablecuz]

yep i lost 1 mark there XD
didnt really notice the 'magnitude' part. so it went straight down left to right lol

dw, that screwed me aswell :mad1:

 

[untouchablecuz]

??
That whole experiment was Thomson finding the charge to mass ratio. Nothing else.

I completely screwed the hydrogen spectra experiment question. FML

yes

but the question asked how he used his apparatus to settle the debate over the nature of cathode rays

he used it to calculate q/m, which in turn means that because this ratio exists and can be calculated, there must be mass! hence settling the debate

ideal independent answers mention it, but don't go into detail:

"His experiment used both fields with forces balanced allowing him to find a contant value of q/m for all cathode materials and firmly establishing that the rays were particles."

 

[abhi23]

centripital force = magnetic force

i.e. mv^2/r = qvBsinx

r=mv^2/qvBsinx=mv/qBsinx

r is inversely propotional to B i.e. r oc 1/B

hence a greater radius means a weaker B field and vice versa

use this to answer the Q

Beautiful.

 

[marshy01]

Im sitting this test tomorrow were slow up here lol

could anyone give me a run down on the major concepts involved in this test (eg. cathode rays, BCS theory, black body rad. etc ) and Quanta to Quarks option

thank you