HSC Physics Question Thread

[Adriaclya]

Didn't know how to do these questions ... could someone please explain them? Would be much appreciated! Thanks in advanced

Hi! For the second question ie the second picture question??
An induced emf is produced because there is varying magnetic flux or a changing magnetic field relative to the wires - which are conductors. (This is true beacuse of faraday's law of electromagnetic induction.) The vary in magnetic field can be seen as the loop is moved away.
For the second part of that question, i think the current travels clockwise since the magnetic field is becoming weaker as the conductor moves further away from it. According to lenz's law, the direction of the current should produce a magnetic field that opposes the magnetic field which was induced by the straight current carrying conductor. Yeahhhhhh?
Hope it helps !

[Happy Physics Land]

Didn't know how to do these questions ... could someone please explain them? Would be much appreciated! Thanks in advanced

Hey Jamgoesbam!!!

The solution to your first question has been attached, the answers to your next question would come later. Basically for the first part, I clearly dont have a grid paper for me to draw on. But essentially you should draw just about everything it asks for and perhaps at the landing point you can further identify that the final vertical velocity is greater than the initial vertical velocity under the influence of gravitational field of attraction. The next part is basically a combination of your two formulae: v = u+at and distance = ut + 1/2 at². You can perhaps try the other formula v² = u² + 2a(distance). Thats what I initially intended to do but in the end I decided the first method was the best in this situation. So, there you have it!



Best Regards
Happy Physics Land

[Happy Physics Land]

Didn't know how to do these questions ... could someone please explain them? Would be much appreciated! Thanks in advanced

For your next question. I will type out my answers here.

a) An emf will be induced in the loop because as the loop moves away from the current-carrying wire, there is relative motion between the loop and the magnetic field into the page. Consequently there will be a change in magnetic flux and according to Faraday's law, an emf will be induced. Using right hand palm rule, we can also ascertain that there will be a magnetic force pushing the positive charges downwards and negative charges upwards. As a result, a potential difference (hence emf) is created due to opposite charge accumulations at different ends of the loop.

b) The current direction is clockwise using right hand coil rule. Now this question doesnt require any explanation but I will explain here anyways. As the loop moves away from the wire, the magnetic field density decreases and hence there is less into the page magnetic flux penetrating through the loop. Therefore Lenz's law states that the current flow induced in the loop will be in a clockwise direction to compensate for the loss in magnetic flux into the page.

[Happy Physics Land]

Didn't know how to do these questions ... could someone please explain them? Would be much appreciated! Thanks in advanced

This last question is relatively difficult. Many people struggle to understand the relationship between stopping potential, work function and kinetic energy because they are so closely connected. But at the same time it is absolutely essential to distinguish between them because they are, after all, different concepts. So before I start explaining, I would just like to point out some essential things about this experiment and about these concepts.

Maximum E_k = hf_{incident light} - Work function
Stopping voltage = minimum energy required to stop photocurrent from reaching the receiver (E=qV)

Just a sidenote, the circuit is connected in such a way that the receiver is attached to a negative potential and hence repels photoelectrons that try to come towards it. Essentially a current can only emerge if maximum kinetic energy can overcome the energy produced by stopping potential (E=qV). With these information in mind, I have attached my solution below and you can have a look for yourself. This is a challenging topic and in case if l get the answer wrong or if you dont understand anything please ask and I will be happy to help!



Best Regards
Happy Physics Land

[Happy Physics Land]

Hey,
does anyone have concise notes on this dotpoint:
process information to discuss Einstein and Planck’s differing views about whether science research is removed from social and political forces
Thanks!

Hey Sahar!

Yep yep this is one of those really tedious physics dotpoints that ask for the relationship between science, society and politics. Before I start, I must emphasise that despite how bs this can be, the syllabus wants us to recognise the disastrous impact science can have on the society even though it was never intended to cause these outcomes. Anyways,

Max Planck and Albert Einstein are similar in that:

- Both were leaders in the quantum physics field
- Both were born in Germany
- Both were involved in developing atomic bombs
- Both campaigned for the use of science in wars and politics
- Both were devoted to science however fail to recognise the adverse impacts of these scientific developments

Differences:

- Einstein was a pacifist, Planck was a nationalist
- Planck signed a document supporting the justification of war for Germany, Einstein refuses to sign the same document and instead signed an anti-war manifesto
- Planck was incredibly patriotic whereas Einstein called nationalism an infantile disease
- Planck was well-renowned scientist in Germany but Einstein was more famous worldwide and received little prestige within Germany because he opposed Germany's military actions
- Einstein served for Americans but Planck served for Germany
- Planck pursued science for his country but Einstein recognises science as a human endeavour

Conclusively, even though Einstein and Planck in their normal lives are very close friends, their political aspirations and scientific views differ. Evidently, science is closely related to politics and war in a variety of ways.

[Swagadaktal]

Hey Sahar!

Yep yep this is one of those really tedious physics dotpoints that ask for the relationship between science, society and politics. Before I start, I must emphasise that despite how bs this can be, the syllabus wants us to recognise the disastrous impact science can have on the society even though it was never intended to cause these outcomes. Anyways,

Max Planck and Albert Einstein are similar in that:

- Both were leaders in the quantum physics field
- Both were born in Germany
- Both were involved in developing atomic bombs
- Both campaigned for the use of science in wars and politics
- Both were devoted to science however fail to recognise the adverse impacts of these scientific developments

Differences:

- Einstein was a pacifist, Planck was a nationalist
- Planck signed a document supporting the justification of war for Germany, Einstein refuses to sign the same document and instead signed an anti-war manifesto
- Planck was incredibly patriotic whereas Einstein called nationalism an infantile disease
- Planck was well-renowned scientist in Germany but Einstein was more famous worldwide and received little prestige within Germany because he opposed Germany's military actions
- Einstein served for Americans but Planck served for Germany
- Planck pursued science for his country but Einstein recognises science as a human endeavour

Conclusively, even though Einstein and Planck in their normal lives are very close friends, their political aspirations and scientific views differ. Evidently, science is closely related to politics and war in a variety of ways.

WAIT WTF DO YOU HAVE TO RELATE POLITICS IN PHYSICS?

soz from vce here... do you have to study the life of scientists and view their achievements through their position in society?  Is this examinable or just in sacs (in school tests)

Pwoah just really awestruck here lol.

=

[Sahar8642]

Hey Sahar!

Yep yep this is one of those really tedious physics dotpoints that ask for the relationship between science, society and politics. Before I start, I must emphasise that despite how bs this can be, the syllabus wants us to recognise the disastrous impact science can have on the society even though it was never intended to cause these outcomes. Anyways,

Max Planck and Albert Einstein are similar in that:

- Both were leaders in the quantum physics field
- Both were born in Germany
- Both were involved in developing atomic bombs
- Both campaigned for the use of science in wars and politics
- Both were devoted to science however fail to recognise the adverse impacts of these scientific developments

Differences:

- Einstein was a pacifist, Planck was a nationalist
- Planck signed a document supporting the justification of war for Germany, Einstein refuses to sign the same document and instead signed an anti-war manifesto
- Planck was incredibly patriotic whereas Einstein called nationalism an infantile disease
- Planck was well-renowned scientist in Germany but Einstein was more famous worldwide and received little prestige within Germany because he opposed Germany's military actions
- Einstein served for Americans but Planck served for Germany
- Planck pursued science for his country but Einstein recognises science as a human endeavour

Conclusively, even though Einstein and Planck in their normal lives are very close friends, their political aspirations and scientific views differ. Evidently, science is closely related to politics and war in a variety of ways.

Thank You so much!

[RuiAce]

WAIT WTF DO YOU HAVE TO RELATE POLITICS IN PHYSICS?

soz from vce here... do you have to study the life of scientists and view their achievements through their position in society?  Is this examinable or just in sacs (in school tests)

Pwoah just really awestruck here lol.

=

Do you reckon I'm an advocate for the current physics course?

They had to reduce its difficulty so that general maths students would not be deterred from enrolling. An immediate drawback is in how there is much more emphasis on the social context of physics and chemistry than actual physics/chemistry.

[jamgoesbam]

This last question is relatively difficult. Many people struggle to understand the relationship between stopping potential, work function and kinetic energy because they are so closely connected. But at the same time it is absolutely essential to distinguish between them because they are, after all, different concepts. So before I start explaining, I would just like to point out some essential things about this experiment and about these concepts.

Maximum E_k = hf_{incident light} - Work function
Stopping voltage = minimum energy required to stop photocurrent from reaching the receiver (E=qV)

Just a sidenote, the circuit is connected in such a way that the receiver is attached to a negative potential and hence repels photoelectrons that try to come towards it. Essentially a current can only emerge if maximum kinetic energy can overcome the energy produced by stopping potential (E=qV). With these information in mind, I have attached my solution below and you can have a look for yourself. This is a challenging topic and in case if l get the answer wrong or if you dont understand anything please ask and I will be happy to help!

(Image removed from quote.)

Best Regards
Happy Physics Land

Hey Happy Physics Land,
Thanks heaps for your answers - explained things much more clearly to me than the answers! Just for the last question though, about the photoelectric effect, they changes it back into eV (just fyi)! Other than that, awesome effort

[jamonwindeyer]

Do you reckon I'm an advocate for the current physics course?

They had to reduce its difficulty so that general maths students would not be deterred from enrolling. An immediate drawback is in how there is much more emphasis on the social context of physics and chemistry than actual physics/chemistry.

Will vouch for fact that (and I chatted about this in my lecture today) HSC Physics does not get you prepared for university physics very well at all. I'm all for the current course because it is accessible to everyone and I think getting everyone interested in science is awesome!! 

That said, I've heard rumours of a Physics Extension course being developed that is more mathematical, and I would be a big fan of such a course ! 

Edit: Do still dislike the social aspect, not in principle, but in just how often it is integrated. I think it is important for scientists to consider the social impacts of their actions, but yeah, too much for my taste.

[RuiAce]

Will vouch for fact that (and I chatted about this in my lecture today) HSC Physics does not get you prepared for university physics very well at all. I'm all for the current course because it is accessible to everyone and I think getting everyone interested in science is awesome!! 

That said, I've heard rumours of a Physics Extension course being developed that is more mathematical, and I would be a big fan of such a course ! 

Edit: Do still dislike the social aspect, not in principle, but in just how often it is integrated. I think it is important for scientists to consider the social impacts of their actions, but yeah, too much for my taste.

Really curious as to what physics extension will be like

[jamonwindeyer]

Hey,
Does anyone have detailed notes on the practicals as we never covered them in school properly. As in, we watched while the teacher did the prac and didn't do proper write-ups
Thanks!

Hey! Totally don't mean to do a sell of the notes I wrote, but all the practicals you need for the exam are covered in the ATAR Notes Physics HSC Notes (they cost $25.00). To be honest, I haven't seen much on the practicals outside of those notes, but keep in mind you won't need too much on them for the exam! Just an understanding of the physics principles involved at the basic level (check the syllabus for the details as to which practicals you need) 

[Happy Physics Land]

Will vouch for fact that (and I chatted about this in my lecture today) HSC Physics does not get you prepared for university physics very well at all. I'm all for the current course because it is accessible to everyone and I think getting everyone interested in science is awesome!! 

That said, I've heard rumours of a Physics Extension course being developed that is more mathematical, and I would be a big fan of such a course ! 

Edit: Do still dislike the social aspect, not in principle, but in just how often it is integrated. I think it is important for scientists to consider the social impacts of their actions, but yeah, too much for my taste.

I also heard rumours about BOSTES changing the physics syllabus in 2018

[RuiAce]

I also heard rumours about BOSTES changing the physics syllabus in 2018

Well it's about time they got rid of stuff like TVs and old definition of Meissner effect and so on

[brontem]

Do you reckon I'm an advocate for the current physics course?

They had to reduce its difficulty so that general maths students would not be deterred from enrolling. An immediate drawback is in how there is much more emphasis on the social context of physics and chemistry than actual physics/chemistry.

I'm going to blow in here and just give my two cents lol    Of course HSC physics is not anywhere near uni level physics, they can't expect people to do uni level stuff in year 12 and excel at it.. how much actual physics and chemistry could possibly be squeezed into the curriculum? not to mention that a lot of the stuff everyone gets taught, regardless of the maths involved, is wrong
Obviously not doing high level maths could be a drawback, if you commit to doing HSC physics then you can commit to putting in the extra effort for the maths involved, but don't go blaming us general kids for all the wordy crap in exams, we don't like it either   
_{please don't hate me}