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The real CONFIRMED mc answers (1 Viewer)

Tellytubby

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bucca.sam said:
12 is a not b

Hertz incorrectly showed that the rays were not deflected by electric fields.
The paddle wheel experiment shows that the rays hold momentum, and therefore have mass - showing they are of particle nature.

They were shown to be deflected by electric fields later on when the technology of making vacuum tubes improved.

:spam: therefore 12 is A
This doesn't prove it's a charged particle. Light has momentum too, it will propel a solar sail. Showing the beam has momentum does not prove that it is a charged particle.

In regard to question 4 I rearranged delta y=ut + 1/2at^2 to get t=sqrt(h/0.5a) then plugged in a few linear values for h and saw it wasn't increasing in a linear fashion.
 

poisonives

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cookiemonsterz said:
The question is asking about charged particles, proving they had momentum does not proved they are charged particles but rather normal particles. Initially they were thought to be non-charged particles as you said, and it was not untill JJ Thompson successfully deflected them with an electric field were they proven to be charged.

:spam: therefore the answer is B
well ur right, but i think this question is annoying. hear me out..

from what my teacher KEPT saying to me, the paddle wheel experiment CONFIRMED that cathode rays were particles, since they have momentum, and waves cannot have momentum.

Thus, this proves that cathode rays are NOT electromagnetic waves. And if we manipulate the language of the question, we can infer that since they are NOT waves, they must be charged particles. While the experiment itself doesn't tell us that it is a charged particle, we can infer it due to the magnetic field experiment
 

heybashme

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What do people think of question 5?? orignally i put c then i put a because shouldnt time dilate for an object travelling at near light speeds??? nearly my whole class said otherwise im confused what did you guys get?
 

Aaron.Judd

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heybashme said:
What do people think of question 5?? orignally i put c then i put a because shouldnt time dilate for an object travelling at near light speeds??? nearly my whole class said otherwise im confused what did you guys get?
We all agree c is correct.
 

Kings407

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poisonives said:
well ur right, but i think this question is annoying. hear me out..

from what my teacher KEPT saying to me, the paddle wheel experiment CONFIRMED that cathode rays were particles, since they have momentum, and waves cannot have momentum.

Thus, this proves that cathode rays are NOT electromagnetic waves. And if we manipulate the language of the question, we can infer that since they are NOT waves, they must be charged particles. While the experiment itself doesn't tell us that it is a charged particle, we can infer it due to the magnetic field experiment

i agree with you.... we did the paddle wheel experiment in class to prove cathode rays are particles.... so going on as poisonives said you can infer the answer is a from the question.
 

dolbinau

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Kings407 said:
i agree with you.... we did the paddle wheel experiment in class to prove cathode rays are particles.... so going on as poisonives said you can infer the answer is a from the question.

This proves they are particles, not charged particles. Other experiments (hertz) incorrectly showed they were NOT deflected in an electric field so this experiment+paddle wheel would just show they are particles not charged particles.
 

poisonives

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dolbinau said:
This proves they are particles, not charged particles. Other experiments (hertz) incorrectly showed they were NOT deflected in an electric field so this experiment+paddle wheel would just show they are particles not charged particles.
but they knew that IF the cathode rays were particles, they would be charged since they were deflected in a magnetic field?
 

dolbinau

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You should consider that B is the most correct answer, even if there are redeeming qualities of A.

If Crookes showed that they were deflected in magnetic field or on paddle wheel, but then Hertz showed they were not deflected in a magnetic field what can you think? It took JJ. Thomson's experiment to conclude (CSSA 2008 trial official answeres confirms he ended the debate too)
 

poisonives

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dolbinau said:
You should consider that B is the most correct answer, even if there are redeeming qualities of A.

If Crookes showed that they were deflected in magnetic field or on paddle wheel, but then Hertz showed they were not deflected in a magnetic field what can you think? It took JJ. Thomson's experiment to conclude (CSSA 2008 trial official answeres confirms he ended the debate too)
Hertz showed that they were not deflected in ELECTRIC FIELDS. look, i agree A is probably the best answer, but i need to vent...they should pay B as well :cold: ... thats meant to be a sad smiley but i can't be fucked finding it
edit: i meant b for a, a for b
 
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pdoueihi said:
dude... ur a lunatic u just copied my thread... what they were confirmed on my thread so now theyre "real confirmed" for ur thread.... pfft what a tool
lol im such a cyber bully.

At the time i made this you had not yet updated urs to the correct answers, so i thought it would be useful for people to have all the answers clearly defined without needing to read 3 pages of your thread.

btw i actually posted this list in another thread before you even made urs, the only thing i copied was the name, put real in front of it.
 

dolbinau

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poisonives said:
Hertz showed that they were not deflected in ELECTRIC FIELDS. look, i agree A is probably the best answer, but i need to vent...they should pay B as well :cold: ... thats meant to be a sad smiley but i can't be fucked finding it
edit: i meant b for a, a for b
Yeah electric fields* same thing. (not literally but you know, lol)

There was a wikipedia quote somewhere which explained it all..
 

akukei

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poisonives said:
but they knew that IF the cathode rays were particles, they would be charged since they were deflected in a magnetic field?
Yes, however this observation was contradicted by Hertz's observation that they were NOT deflected by an electric field. Thompson's observation, at a later date, that they were deflected by electric fields showed that Hertz was wrong thus 'resolving' the debate.
 

f(sex)

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ARGH I LOST A MARK ON QUESTION 14 WTF IS WRONG WITH ME
ELECTROSTATIC IS WRONG WRONG WRONG
its this helpless feeling that i have now
 

dolbinau

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f(sex) said:
ARGH I LOST A MARK ON QUESTION 14 WTF IS WRONG WITH ME
ELECTROSTATIC IS WRONG WRONG WRONG
its this helpless feeling that i have now
It's one mark.
 

Ginny11

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i dont understand 13...shouldn't it be 'b'? coz i worked it out by finding its frequency and then finding its energy by e=hf?
Also whats the go with 5? shouldt it be D? when ya use time dilation formula it came up with D?
 
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westkikass

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Lol each nanometre is 10^-9 metres zzz forgot about that n failed the question.
 

Shadose

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Didn't check though, I definitely got 15 wrong though, where I chose A. Had no time at the end (nearly forgot to finish the multiple choice) and made a quick logical guess. Which it obviously appears is not.
 

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