HSC Physics Question Thread

[RuiAce]

I saw this as well, it looks like it's a tad beyond HSC scope, but for the original poster, it does (can't vouch for accuracy) say that Type 1's are used in SQUID Magnetometers 

At a physics day at USyd (compulsory school excursion) when they were talking about superconductors they did mention SQUID and what it stood for, but nothing about it.

[jamonwindeyer]

At a physics day at USyd (compulsory school excursion) when they were talking about superconductors they did mention SQUID and what it stood for, but nothing about it.

Yep I have no idea how they work, only that they are extremely sensitive magnetometers used in quantum research. That's all I knew back in the HSC too, so you definitely don't need any more than that 

I'll link to Wikipedia for SQUID though, in case anyone is curious, it seems to go through some pretty complex theory that I'm not overly familiar with 

[Ahsun]

Imagine you are the structural engineer at NASA  for the design of a new moon landing module (not the rocket). You need to find the best unmanned module design to use for safe landing on the surface of the moon.
Plan, choose equipment or resources for a hypothetical first hand investigation to
propose a design. Include free-hand sketch or a draw app for illustrating your design and briefly describe how you would test the module landing.

I have  a design of the landing module but not sure how to test the module landing exactly

[jamonwindeyer]

Imagine you are the structural engineer at NASA  for the design of a new moon landing module (not the rocket). You need to find the best unmanned module design to use for safe landing on the surface of the moon.
Plan, choose equipment or resources for a hypothetical first hand investigation to
propose a design. Include free-hand sketch or a draw app for illustrating your design and briefly describe how you would test the module landing.

I have  a design of the landing module but not sure how to test the module landing exactly

Hey Ahsun! I'm not sure about this one, there would be a lot to test! I suppose the most important thing would be durability, perhaps you'd be looking at some sort of test where you drop the prototype module from different heights (in moon-like conditions) and determine the best design based on which can be dropped from the greatest height?

Hmm... That's about all I can think of right now!! I'll let you know if I come up with something else though 

[Ahsun]

Hey Ahsun! I'm not sure about this one, there would be a lot to test! I suppose the most important thing would be durability, perhaps you'd be looking at some sort of test where you drop the prototype module from different heights (in moon-like conditions) and determine the best design based on which can be dropped from the greatest height?

Hmm... That's about all I can think of right now!! I'll let you know if I come up with something else though 

Thanks for the ideas

[jamonwindeyer]

Thanks for the ideas

No problem! Someone else might have better ones than me if anyone wants to chip in 

[Happy Physics Land]

Imagine you are the structural engineer at NASA  for the design of a new moon landing module (not the rocket). You need to find the best unmanned module design to use for safe landing on the surface of the moon.
Plan, choose equipment or resources for a hypothetical first hand investigation to
propose a design. Include free-hand sketch or a draw app for illustrating your design and briefly describe how you would test the module landing.

I have  a design of the landing module but not sure how to test the module landing exactly

Hey ahsun!

An important thing about the module would be to make it out of a material that would be resistant against the effect of solar wind, and ensure that the internal parts are more robust against discharge arcs. Perhaps you can add protective coatings that can make electronic parts inside to be less vulnerable to solar wind radiations. Another aspect I would mention is more so the material science side of things. Firstly you would want your landing module to have 3 "legs" (tripod design) or 4 "legs" stand design. These stands can be made out of high strength to weight ratio aluminium alloys (after all, landing modules are quite massive and to minimise fuel cost on rockets you would wanna minimise weight). In fact majority of the landing module would be made out of titanium alloy or aluminium alloy for the same reasons. To ensure the strength of the entire module you would want to have a warren truss structure for the structural components such as the stand. When you are considering landing you must consider about the gravity of the moon, projectile motion principles (You can perhaps make up a situation and perform some calculations around it).

Hope the information helps!

Best Regards
Happy Physics Land

[wyzard]

Imagine you are the structural engineer at NASA  for the design of a new moon landing module (not the rocket). You need to find the best unmanned module design to use for safe landing on the surface of the moon.
Plan, choose equipment or resources for a hypothetical first hand investigation to
propose a design. Include free-hand sketch or a draw app for illustrating your design and briefly describe how you would test the module landing.

I have  a design of the landing module but not sure how to test the module landing exactly

Sounds pretty interesting. You can't really test the actual landing module on the moon of course. What you can do instead is to simulate the landing conditions. You can to consider at what speed will the landing module touch down and maybe the 'hardness' of the moon surface (think landing on hard concrete surface vs. grass).

With this simulated environment, you can then test out several different designs.

[jamonwindeyer]

Great ideas HPL and wyzard!! 

[conic curve]

So I really suck at maths physics and currently I'm doing the intensity square law and am finding it difficult (especially the maths to it). Could someone here please give me advice on how I should approach the inverse square law?

Thanks

[Swagadaktal]

So I really suck at maths physics and currently I'm doing the intensity square law and am finding it difficult (especially the maths to it). Could someone here please give me advice on how I should approach the inverse square law?

Thanks

Not sure how much you're meant to know within the HSC syllabus, but essentially the ratio of sound intensity is related in this fashion:
I = 1/r^2 (this is about sound right? if this is a diff  topic awks lmao)

So basically for a distance travelled of x m, the intensity decreases by a factor of x^2.

So if you travel 2 metres away from the source, the sound intensity decreases by a factor of 4 ( so divide by four)

[jamonwindeyer]

Not sure how much you're meant to know within the HSC syllabus, but essentially the ratio of sound intensity is related in this fashion:
I = 1/r^2 (this is about sound right? if this is a diff  topic awks lmao)

So basically for a distance travelled of x m, the intensity decreases by a factor of x^2.

So if you travel 2 metres away from the source, the sound intensity decreases by a factor of 4 ( so divide by four)

This is a great example!

In terms of the mathematics behind it, this diagram might help! The best way to consider it is in terms of the surface area of a sphere with varying radius (formula below). If you double the radius, you quadruple the surface area. In terms of the inverse square law, this corresponds to some amount of energy being 'spread' over four times a larger area, and thus, being a quarter of the intensity. Intensity decreases in proportion to the square of the radius, and so:

[Swagadaktal]

This is a great example!

In terms of the mathematics behind it, this diagram might help! The best way to consider it is in terms of the surface area of a sphere with varying radius (formula below). If you double the radius, you quadruple the surface area. In terms of the inverse square law, this corresponds to some amount of energy being 'spread' over four times a larger area, and thus, being a quarter of the intensity. Intensity decreases in proportion to the square of the radius, and so:



(Image removed from quote.)

yeah that works too
hehe you guys are honestly amazing with your explanations

[conic curve]

So I'm having trouble with the following Inverse square law questions (there are actually much more than this)

1. A slide projector produces a rectangular image which has the dimensions 0.300m wide and 0.200m high when the projector is 0.500 from the screen. How far from the screen would the projector have to be placed in order to fill a screen 1.500 wide?
2. How will the intensity of the light falling on a surface be affected if the source of the light is moved to twice its original distance?
3. How will the intensity of the light falling on a surface be affected if the source of the light is moved to twice its original distance?

If someone could provide me with an indepth explanation, that'd be great 

Thanks   

[wyzard]

So I'm having trouble with the following Inverse square law questions (there are actually much more than this)

1. A slide projector produces a rectangular image which has the dimensions 0.300m wide and 0.200m high when the projector is 0.500 from the screen. How far from the screen would the projector have to be placed in order to fill a screen 1.500 wide?
2. How will the intensity of the light falling on a surface be affected if the source of the light is moved to twice its original distance?
3. How will the intensity of the light falling on a surface be affected if the source of the light is moved to twice its original distance?

If someone could provide me with an indepth explanation, that'd be great 

Thanks   

1) For the projected rectangular image, the length and height will increase proportional to the distance. So to have increase the width from 0.300m to 1.500m, you increase increase the distance five times.
2) As the length and height both increase proportional to the distance, this means that the area will increase proportional to the distance squared, as area is the product of length and height. Hence the light will spread out in the area, resulting in the intensity falling at a greater distance, being inversely proportional to the distance squared. So by doubling the distance, you decrease the intensity 4 times.
3) Just a repeat of Q2.

Hope this helps!