Physics Predictions/Thoughts (7 Viewers)

[coolcat6778]

Q32 is not a history question are you retarded

"reference to experimental evidence"

hmm I wonder which experiments? oh yes, the ones we were forced to rote learn

 

[coolcat6778]

Lol did you author this exam, is that why you're so triggered?

 

[AAArated]

seriously, insulting me doesn't change the fact that these aren't actual physics questions...

YOU DO NOT KNOW WHAT ACTUAL PHYSICS QUESTIONS ARE BECAUSE YOU ARE A LOW BAND 5 HIGHSCHOOL PHYSICS STUDENT YOU HAVE NO IDEA WHAT HAPPENS AT A UNIVERSITY OR POST UNIVERSITY LEVEL YOU ARE JUST ATTEMPTING TO JUSTIFY YOUR STUPIDITY

 

[coolcat6778]

YOU DO NOT KNOW WHAT ACTUAL PHYSICS QUESTIONS ARE BECAUSE YOU ARE A LOW BAND 5 HIGHSCHOOL PHYSICS STUDENT YOU HAVE NO IDEA WHAT HAPPENS AT A UNIVERSITY OR POST UNIVERSITY LEVEL YOU ARE JUST ATTEMPTING TO JUSTIFY YOUR STUPIDITY

shhh. mid band 5. thanks assessment mark

 

[AAArated]

Lol did you author this exam, is that why you're so triggered?

the same opinions from anyone else would be fine you're just a deluded retard though

 

[coolcat6778]

an actual physics question isn't one that makes you write a 30 liner essay (x3). with how stupid I am I still know what physics is and what humanities is.

 

[cheesynooby]

Does anyone feel the very last (non history) question is a load of bullshit?

what the fuck is this answer even doing? "Analyse the subsequent motion" is a fucking horrible way to phrase an apparently quantitative question

i don't get why you think that answer is bad?
i think 'analyse' is just nesa's way of saying 'tell us everything you think is relevant and back it up with calcs where possible'

 

[coolcat6778]

the same opinions from anyone else would be fine you're just a deluded retard though

stop being so ableist mate I have cerebral palsy

 

[coolcat6778]

they blame the world around them for their stupidity

sorry, where exactly did I do this lmao

Complaining that the physics exams are just writing exams (obviously true) isn't blaming others for my stupidity



Say what you want, these questions ARE inherently history questions mixed with a bit of theory. However,

Keywords suggesting they ARE history/humanities questions
31:
"Assess the contribution of the results ... in developing an understanding ..."

32:
this one is less history but still it is a full page essay

33:
"Analyse the role of experimental evidence and theoretical ideas in developing the standard model of matter"

 

[AAArated]

an actual physics question isn't one that makes you write a 30 liner essay (x3). with how stupid I am I still know what physics is and what humanities is.

sigh

 

[Tryingtodowell]

ahhh yes the 50% HSC physics and maths student making claims about what happens at a university level

2019 dude
do u know when the raw marks -aligned thing for 2025 officially comes out?

 

[AAArated]

2019 dude
do u know when the raw marks -aligned thing for 2025 officially comes out?

after your results come out it's made based on inputs from different students that bought their raw marks

 

[BionicMango]

2019 dude
do u know when the raw marks -aligned thing for 2025 officially comes out?

Basically some people buy the raw marks results after the results come out and give them to the raw marks database for our benefit. So anytime dec 18th onwards

 

[coolcat6778]

i don't get why you think that answer is bad?
i think 'analyse' is just nesa's way of saying 'tell us everything you think is relevant and back it up with calcs where possible'

Because the was no indication we had to calculate anything (it only said to mention to relevant laws and formulas, not use).
Hence, I don't believe they should reduce marks for a full qualitative response which mentions the laws

Want another crazy (and wrong sample solution)?



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It will clearly follow a elliptical orbit (not escape like what the retarded official solutions suggest)
Along with that, this is clearly an "Explain" question. So I don't fucking know why the official solutions even put calculations (that don't even prove anything) cause clearly their answer is wrong.

 

[coolcat6778]

Also being asked to mention formulas or laws doesn't make a question quantitative. In the 2024 paper, there were many questions where you had to refer to principles and formulas (but were not required to make any calculations) in which I did full mark most of them without calculations or numbers.

Hence there was nothing indicating that the very last 2025 physics question required the use of calculations...

seriously if they wanted to make it a quantitative question, the least they would do was provide you the radius and other relevant statistics (to ensure everyone's final answer is in agreement). This isn't business studies like come on, do you deadass think we need to memorise the height of a stationary orbit? Like even if this value was needed, it would've been on the formula sheet (like all the other important numbers) or given in the question itself.

 

[BionicMango]

Because the was no indication we had to calculate anything (it only said to mention to relevant laws and formulas, not use).
Hence, I don't believe they should reduce marks for a full qualitative response which mentions the laws

Want another crazy (and wrong sample solution)?

View attachment 50541
View attachment 50542
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View attachment 50543
________________________________________________________________________________________________________
It will clearly follow a elliptical orbit (not escape like what the retarded official solutions suggest)
Along with that, this is clearly an "Explain" question. So I don't fucking know why the official solutions even put calculations (that don't even prove anything) cause clearly their answer is wrong.

They won’t necessarily mark down a qualitative answer, these aren’t the solutions given by NESA.

Last questions for 2023 had a bad solution, I disagree completely with it (thank goodness for the “answers could include”)

 

[lucas10champ]

Does anyone feel the very last (non history) question is a load of bullshit?

The satellite is in a geostationary orbit thus the velocity and radius can be determined as it is stationary relative to a point on Earth (T = 24 hours). Applying Kepler’s 3rd Law to find orbital radius from known period: r3 / T2 = GM / 4π2 r = 3√(GMT2 / 4π2) r = 3√{6.67 x 10-11 x 6.0 x 1024 x (24 x 60 x 60)2 / 4π2} r = 4.2297… x 107 m r = 4.2 x 107 m (2 s.f.) from the centre of Earth Determining orbital velocity by applying formula: Fc = Fg → mv2 / r = GMm / r2 vorb = √(GM / r) vorb = √(6.67 x 10-11 x 6.0 x 1024 / 4.2297… x 107) vorb = 3075.9627… ms-1 vorb = 3100 ms-1 (2 s.f.) An explosion can be analysed using the law of conservation of momentum. Whilst kinetic energy is not necessarily conserved, momentum is always conserved in any closed system interaction. Hence: Σpi = Σpf pa initial + pb initial = pa final + pb final As their mass is identical, it will be denoted with m: mv + mv = m(2v) + mva 2mv = 2mv + mvb mvb = 0 Thus, vb = 0. If ma changes from v to 2v = 2 x 3075.9627… = 6151.925… = 6200 ms-1 (2 s.f.), then it carries all of the initial momentum and mb is left with no momentum and thus no velocity after the explosion. Considering the initial and final kinetic energies: ΣKi = ½mv2 + ½mv2 = mv2 ΣKf = ½m(2v)2 + 0 = 2mv2 Hence, it can be determined that the satellite pieces experienced an increase in kinetic energy of mv2. By the law of conservation of energy, this extra energy likely came from chemical potential energy in the explosion. Analysing the subsequent motion of ma: ma was originally at orbital velocity v given by v = √(GM / r). Doubling the velocity results in its velocity being v = 2√(GM / r) = √(4GM / r). Comparing this to escape velocity which can be derived by: Ei = Ef Ki + Ui = Kf + Uf Escape velocity is where the mass has no kinetic energy remaining once it reaches r = infinity where U = 0: Ki + Ui = 0 (Kf = 0, Uf = 0) ½mv2 + (-GMm / r) = 0 v = √(2GM / r) v = √(2 x 6.67 x 10-11 x 6.0 x 1024 / (4.2297… x 107)) v = 4350.095… ms-1 v = 4400 ms-1 (2 s.f.) Hence, the new velocity of ma being 2v = 6200 ms-1 is larger than escape velocity of √(2GM / r) = 4400 ms-1. This means that ma will travel in a hyperbolic path away from the Earth and never return. As it travels away its total mechanical energy will remain constant as per the law of conservation of energy: E = K + U. However, as it travels further away, its potential energy increases by U = -GMm / r and thus its kinetic energy decreases to conserve E. As kinetic energy is given by K = ½mv2, its speed will decrease as it travels further away. Because potential energy asymptotes to zero as ma approaches an infinite distance away, the kinetic energy and thus speed will asymptote to a positive, non-zero value as its initial energy exceeds what is needed for escape velocity. This can be shown as follows: Ki + Ui = Kf (Uf = 0) ½mv2 = ½mu2 + (-GMm / r) ½mv2 = 2GMm / r - GMm / r = GMm / r v = √(2GM / r) = 4350.095… ms-1 = 4400 ms-1 (2s.f.) Hence, ma will slow down asymptoting to a speed of 4400 ms-1 as it approaches a point infinitely far from the Earth, ignoring the influence of other gravitational fields in the universe. Analysing the subsequent motion of mb: mb has a velocity of 0 after the explosion as derived earlier. The only force acting on it is the gravitational force F = GMm / r2 from the Earth which will be vertically downwards towards the centre of the Earth. Hence, the acceleration is in the same direction. Given that its velocity is zero, it will simply accelerate downwards towards the centre of the Earth crashing into the surface. Applying the law of conservation of energy, mb will have its total mechanical energy E = K + U remain constant. As it accelerates downwards U will decrease by U = -GMm / r, thus, kinetic energy will increase proportionally. By K = ½mv2, mb will continuously increase speed travelling in a straight line until it impacts the ground. Ei = Ef Ui + Ki = Uf + Kf -GMm / ri + 0 = -GMm / rf + ½mv2 -GM / ri = -GM / rf + ½v2 v = √2(GM / rf - GM / ri) = √2GM(1 / rf - 1 / ri) v = √2 x 6.67 x 10-11 x 6.0 x 1024 x (1 / (6.371 x 106) - 1 / (4.23 x 107)) v = 10330 ms-1 = 1.0 x 104 ms-1 at impact ---

what the fuck is this answer even doing? "Analyse the subsequent motion" is a fucking horrible way to phrase an apparently quantitative question

nah this all sounds right and is what i got

 

[BionicMango]

The key details are:
- geostationary (you can find orbital velocity from there)
- conservation of momentum, so the mb just falls back down to earth while the ma mass starts undergoing an elliptical orbit with the earth at one focus
- kinetic energy not conserved (though I have to reread the question to make sure whether that’s in there or not)

 

[lucas10champ]

The key details are:
- geostationary (you can find orbital velocity from there)
- conservation of momentum, so the mb just falls back down to earth while the ma mass starts undergoing an elliptical orbit with the earth at one focus
- kinetic energy not conserved (though I have to reread the question to make sure whether that’s in there or not)

nah Ma has velocity that is greater than escape velocity so it wont stay in orbit

 

[Arnav_2007]

What’s maximum possible marks for purely qualitative answer for last question? No calculations but including formulas and the conservation of momentum?