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Physics Predictions/Thoughts (1 Viewer)

Balajanovski

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Correct me if I’m wrong, did they also forget to mention the debunking or ‘erroneous’ existence of the luminiferous ether? Because I remember mentioning that but I don’t think I saw them mention it, unless I’m recalling incorrectly
They did not mention it. The sample answer was surprisingly brief.

I think its safe to conclude from the replies that it was just a badly made question.
 

TheOnePheeph

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Correct me if I’m wrong, did they also forget to mention the debunking or ‘erroneous’ existence of the luminiferous ether? Because I remember mentioning that but I don’t think I saw them mention it, unless I’m recalling incorrectly
I don't recall it either. I think I also mentioned that in my answer, because while it didn't really directly prove the speed of light was constant, it definitely was validation for ideas in SR.
 

Arrowshaft

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They did not mention it. The sample answer was surprisingly brief.

I think its safe to conclude from the replies that it was just a badly made question.
Agreed. I think the most accurate paper so far has to be the PEM trial, although it is riddled with errors.
 

Balajanovski

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I’m going to be flat out honest with you, if I was a student who hadn’t known about the work of Pauli, there was NO WAY my mind would jump to the conclusion that there had to be the existence of another particle emitted from beta decay, it’s just too much for a high school student. Also, previous syllabus Q2Q questions were even less rigorous AND they provided more detail
Are you not meant to know that in beta minus decay an anti-neutrino is also released?
 

Arrowshaft

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I don't recall it either. I think I also mentioned that in my answer, because while it didn't really directly prove the speed of light was constant, it definitely was validation for ideas in SR.
It did validate SR. Recall Einstein’s first postulate: the speed of light is constant in all frames of reference, now if the luminiferous ether were present that would indicate that there is a favoured reference frame; which simply cannot be true according to Einstein. But yeah, it is a vague linking point.
 
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Arrowshaft

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Are you not meant to know that in beta minus decay an anti-neutrino is also released?
I don’t think neutrinos are part of the syllabus, I learnt it however but pretty sure my tutor mentioned that neutrinos are one of those topics they could care less about, especially in equations
 

Balajanovski

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From the questions that I have done for practise though, I have found the Excel book's sample papers for physics to be the best.
 

Arrowshaft

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From the questions that I have done for practise though, I have found the Excel book's sample papers for physics to be the best.
Excel also had a lot of question out of the syllabus; at least in my experience with chemistry, I’m not too sure about physics as I just generally rely on past papers and trials. Do you think they could assess simultaneity of relativity as a part of the new syllabus? Because it was favoured in the old syllabus however I haven’t seen them crop up in any sample questions or trials, save the Newcastle Grammar trials
 

TheOnePheeph

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From the questions that I have done for practise though, I have found the Excel book's sample papers for physics to be the best.
Yeah 100%. The funny thing is though the excel papers for chemistry were god awful, I swear half of the content in them was out of syllabus lol.
 

Arrowshaft

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It did validate SR. Recall Einstein’s first posture: the speed of light is constant in all frames of reference, now if the luminiferous ether were present that would indicate that there is a favoured reference frame; which simply cannot be true according to Einstein. But yeah, it is a vague linking point.
Oh sorry! I thought you said “didn’t validate SR” haha. My bad.
 

TheOnePheeph

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Excel also had a lot of question out of the syllabus; at least in my experience with chemistry, I’m not too sure about physics as I just generally rely on past papers and trials. Do you think they could assess simultaneity of relativity as a part of the new syllabus? Because it was favoured in the old syllabus however I haven’t seen them crop up in any sample questions or trials, save the Newcastle Grammar trials
I would say that they can. Just have the classic wrote learned lightning train experiment for that. Just wondering though, if they asked for one of Einstein's thought experiments on the relativity of time, do you think this same thought experiment would be valid to talk about? Or should I wrote learn some other thiught experiments lol?
 

Arrowshaft

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It’s honestly so awful how as the new syllabus we’re left in such a grey area on what we should know and what’s out of the syllabus, and it’s worse when trial paper examiners try to flex their physics knowledge and increase their reputation by including unrelated pieces of trash questions that fit nowhere within the syllabus.
 

Arrowshaft

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I would say that they can. Just have the classic wrote learned lightning train experiment for that. Just wondering though, if they asked for one of Einstein's thought experiments on the relativity of time, do you think this same thought experiment would be valid to talk about? Or should I wrote learn some other thiught experiments lol?
Na that should be fine. Also how in depth are you going with describing it for that? Because I don’t know whether to paint the full picture with the “light clocks” (that can’t exist) or just illustrate a basic framework. Also, with regards to blackbody radiation are you going into full detail with Planck’s idea of quantum oscillators and how it fixed Rayleigh-Jean’s issue on the curve, or are you just mentioning the typical ‘energy is quantised into discrete packets’ kinda thing?
 

TheOnePheeph

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Na that should be fine. Also how in depth are you going with describing it for that? Because I don’t know whether to paint the full picture with the “light clocks” (that can’t exist) or just illustrate a basic framework. Also, with regards to blackbody radiation are you going into full detail with Planck’s idea of quantum oscillators and how it fixed Rayleigh-Jean’s issue on the curve, or are you just mentioning the typical ‘energy is quantised into discrete packets’ kinda thing?
For the relativity thing, I'm just mentioning that the observer experiences the lightning strikes at the same time on the platform since they are stationary and equidistant from the strikes, while someone on the train will experience the strike at the front first since they are moving towards it, meaning the light needs to travel a smaller distance assuming the train is going relativistic speeds. I'm not sure about the light clocks thing you mentioned.

For blackbody radiation Im pretty much just mentioning the "Ultraviolet Catastrophe", where it was expected that as wavelength decreases, according to the wave model of light, since energy increases, there should be no peak wavelength and the intensity should approach infinity, which is not what was observed. I'm then just saying that Planck suggested that light may be quantised into photons, with energy E=nhf, meaning that since there are much less photons with high energies they don't produce as high an intensity, while at higher wavelengths the energy is just a lot lower so the intensity isn't as high. So pretty much the discrete energy packets thing with a little bit more detail and adressing the Rayleigh Jean issue, nothing about the quantum oscillators though.

Btw if I'm incorrect about any of this feel free to correct me, Im pretty much just saying how I understand it at the moment.
 

Arrowshaft

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For the relativity thing, I'm just mentioning that the observer experiences the lightning strikes at the same time on the platform since they are stationary and equidistant from the strikes, while someone on the train will experience the strike at the front first since they are moving towards it, meaning the light needs to travel a smaller distance assuming the train is going relativistic speeds. I'm not sure about the light clocks thing you mentioned.

For blackbody radiation Im pretty much just mentioning the "Ultraviolet Catastrophe", where it was expected that as wavelength decreases, according to the wave model of light, since energy increases, there should be no peak wavelength and the intensity should approach infinity, which is not what was observed. I'm then just saying that Planck suggested that light may be quantised into photons, with energy E=nhf, meaning that since there are much less photons with high energies they don't produce as high an intensity, while at higher wavelengths the energy is just a lot lower so the intensity isn't as high. So pretty much the discrete energy packets thing with a little bit more detail and adressing the Rayleigh Jean issue, nothing about the quantum oscillators though.

Btw if I'm incorrect about any of this feel free to correct me, Im pretty much just saying how I understand it at the moment.
Yeah I’d also tack on the ‘thus violating the law of conservation of energy’ for the UV catastrophe since NESA seems to LOVE that.
 

TheOnePheeph

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Are you not meant to know that in beta minus decay an anti-neutrino is also released?
Sorry didn't see your question before, our teacher taught it to us but I'm not actually sure if its a syllabus dotpoint, but may be good to know anyway
 

Arrowshaft

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Sorry didn't see your question before, our teacher taught it to us but I'm not actually sure if its a syllabus dotpoint, but may be good to know anyway
Yeah. I just hate the way CSSA did it though. It was so demoralising to see that question, I’ve never seen a physics question that hard (given you haven’t already learnt about neutrinos already). They could’ve provided a bit more detail on how neutrinos could were also ejected along with the electrons/positrons
 

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