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March 29, 2024, 06:55:58 am

Author Topic: HSC Physics Question Thread  (Read 1030538 times)  Share 

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RuiAce

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Re: Physics Question Thread
« Reply #945 on: September 29, 2016, 07:35:34 pm »
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Hey Neutron! To properly understand the workings of a transistor is beyond the HSC course. I'm studying transistors now; definitely nothing nice ;) you need to understand PN junctions, but not how they are used in a transistor, so you are all set! I can help you understand PN junctions if that is something you need help with :)

Transistor Radio = Radio that uses transistors in its circuitry (again, no more detail required) ;D

It seems strange that the operation of a transistor isn't covered, but tbh, it's a little too complex to properly understand at Year 12 level :P
Can confirm. My teacher explicitly told us that whilst we needed to know everything about diodes, by contrast virtually nothing about how transistors work

jakesilove

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Re: Physics Question Thread
« Reply #946 on: September 29, 2016, 09:31:56 pm »
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Can confirm. My teacher explicitly told us that whilst we needed to know everything about diodes, by contrast virtually nothing about how transistors work

I spent ages before Trials trying to figure out how transistors work, only to find out explicitly that we can't be asked about them! There's enough complicated stuff in the syllabus to keep you occupied; why make things harder on yourself?
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RuiAce

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Re: Physics Question Thread
« Reply #947 on: September 29, 2016, 09:33:51 pm »
+1
I spent ages before Trials trying to figure out how transistors work, only to find out explicitly that we can't be asked about them! There's enough complicated stuff in the syllabus to keep you occupied; why make things harder on yourself?
On my part, it was because our physics teacher gave us an assignment on transistors before he had taught us the material (purposefully...) and we had to ask him explicitly to end our confusion lel

samuels1999

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Re: Physics Question Thread
« Reply #948 on: September 30, 2016, 12:11:38 am »
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Hi Jamon and Jake

Really appreciate what you do!
I am moving into year 12 next term, and with regard to Physics, do you have any advice on which elective topic is the best to do between "From Quanta to Quarks" and "Medical Physics"?

Thanks
Samuel
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....yeah....its a pretty odd bunch

jamonwindeyer

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Re: Physics Question Thread
« Reply #949 on: September 30, 2016, 01:40:15 am »
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Hi Jamon and Jake

Really appreciate what you do!
I am moving into year 12 next term, and with regard to Physics, do you have any advice on which elective topic is the best to do between "From Quanta to Quarks" and "Medical Physics"?

Thanks
Samuel

Hey Sam! Thanks for your kind words ;D

I'm pretty sure Jake and I would both recommend Medical Physics, we both did it as our Option, and speaking personally it was seriously interesting. More interesting than most of the core (at least for me), and not too difficult either! Quanta to Quarks is more popular though, and so probably has more resources about :)

It doesn't really matter either way; do you get to pick your Option do you? ;D

cherryred

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Re: Physics Question Thread
« Reply #950 on: September 30, 2016, 08:17:50 am »
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Hey,
How would you suggest I draw my diagrams for this question:

A student claims that a DC generator is an ‘electric motor in reverse’.
 
Analyse this claim with reference to the structure and function of a simple DC
 generator and an electric motor.
 
Include diagrams in your answer.

THANK YOU :)

RuiAce

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Re: Physics Question Thread
« Reply #951 on: September 30, 2016, 08:45:03 am »
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Hey,
How would you suggest I draw my diagrams for this question:

A student claims that a DC generator is an ‘electric motor in reverse’.
 
Analyse this claim with reference to the structure and function of a simple DC
 generator and an electric motor.
 
Include diagrams in your answer.

THANK YOU :)
I'll assume you can handle the written part of the response.

For the diagrams, when you draw a DC motor and a DC generator, the bulk of the two diagrams should be identical. You will need an armature, commutator, brushes and the magnetic field in both cases.

The differences lie in thus:


In a motor, we convert electrical energy to kinetic energy. Because electrical energy is what's being converted, we need to draw a battery (cell) connected in a closed circuit to the brushes.

In a generator, we convert kinetic energy to electrical energy. Somehow we must provide the (rotational) kinetic energy, so it really helps to draw an axle for us to rotate. Also, because we usually use a generator to power something up, instead of a battery we will draw a load (this could be a light bulb or many other things).

Spencerr

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Re: Physics Question Thread
« Reply #952 on: September 30, 2016, 11:28:20 am »
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A student claims that a DC generator is an ‘electric motor in reverse’.
Analyse this claim with reference to the structure and function of a simple DC
 generator and an electric motor.

Adding on to Rui's answer, I would suggest that the DC Motor has the Load (where the motor does work as it rotates) and the DC Generators has a handle/ crank which can be rotated to input Mechanical energy. I would say that both the motors and generators use the axle for rotation. Rui's covered the rest :)

I am moving into year 12 next term, and with regard to Physics, do you have any advice on which elective topic is the best to do between "From Quanta to Quarks" and "Medical Physics"?
Samuel

Since I do Q2Q, i'll provide an opposing view :P Q2Q is quite an interesting topic. It's hard to learn at first but afterwards everything fits together neatly and perfectly. Since we study Ideas to Implementation, and we learn about photons etc., Q2Q is just an extension of all that and an understanding of Q2Q really helps mix in with I2I. At this point, I find it difficult to even separate which topics are in which elective because they're so related :)
« Last Edit: September 30, 2016, 11:34:07 am by Spencerr »
1st in HSC Eco 2016

RuiAce

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Physics Question Thread
« Reply #953 on: September 30, 2016, 11:38:03 am »
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Adding on to Rui's answer, I would suggest that the DC Motor has the Load (where the motor does work as it rotates) and the DC Generators has a handle/ crank which can be rotated to input Mechanical energy. I would say that both the motors and generators use the axle for rotation. Rui's covered the rest :)

Since I do Q2Q, i'll provide an opposing view :P Q2Q is quite an interesting topic. It's hard to learn at first but afterwards everything fits together neatly and perfectly. Since we study Ideas to Implementation, and we learn about photons etc., Q2Q is just an extension of all that and an understanding of Q2Q really helps mix in with I2I. At this point, I find it difficult to even separate which topics are in which elective because they're so related :)
Oh my bad. When I meant axle I implicitly included the handle. Thanks for making it more explicit there

But I don't believe an axle is necessary for a motor; in practice I'm pretty sure they are there but for a "simple" motor it's not necessary; the armature can rotate without the motor.

Don't think a simple motor needs to do work either :P

amina_98

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Re: Physics Question Thread
« Reply #954 on: September 30, 2016, 07:21:51 pm »
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Hi guys so my school decided to do the quanta to quarks option this year and a group of classmates found it challenging and decided to study and teach themselves the medical physics option. in our trials however they didnt have a medical phyiscs section so it was left. but obviously in the hsc exam the medical physics questions are going to be there. but the question is will it be marked? will they have to show some sort of "proof" that  they did 30 hours of medical physics study since the course requires 120 hours?
thanks
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ml125

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Re: Physics Question Thread
« Reply #955 on: September 30, 2016, 07:41:26 pm »
+1
Hi guys so my school decided to do the quanta to quarks option this year and a group of classmates found it challenging and decided to study and teach themselves the medical physics option. in our trials however they didnt have a medical phyiscs section so it was left. but obviously in the hsc exam the medical physics questions are going to be there. but the question is will it be marked? will they have to show some sort of "proof" that  they did 30 hours of medical physics study since the course requires 120 hours?
thanks
Whatever option you answer in the hsc will be the one that's marked. It doesn't matter which option you did at school.
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conic curve

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Re: Physics Question Thread
« Reply #956 on: September 30, 2016, 08:22:24 pm »
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Just curious but did an of you find the option harder than the core?

ml125

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Re: Physics Question Thread
« Reply #957 on: September 30, 2016, 09:25:45 pm »
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Just curious but did an of you find the option harder than the core?
Found all of it to be of pretty similar difficulty tbh. Doing Quanta though :D
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Re: Physics Question Thread
« Reply #958 on: October 01, 2016, 01:11:49 pm »
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Found all of it to be of pretty similar difficulty tbh. Doing Quanta though :D

Yay another person doing Quanta (I'm doing it next year though)  :D

RuiAce

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Re: Physics Question Thread
« Reply #959 on: October 01, 2016, 01:12:36 pm »
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Tbh I found astro harder than the core.