HSC Physics Marathon 2013-2015 Archive (7 Viewers)

[duckduckgoose]

re: HSC Physics Marathon Archive

How much do you need to know for the outcomes part of the Syllabus ?

 

[astroman]

re: HSC Physics Marathon Archive

Soz if this sounds super dumb but can u calculate orbital velocity for things that aren't in orbit?

 

[InteGrand]

re: HSC Physics Marathon Archive

Soz if this sounds super dumb but can u calculate orbital velocity for things that aren't in orbit?

What is the wording of the Q (if it's from a paper)? Orbital velocity according to Wikipedia is:

''the speed at which it orbits around the barycenter of a system, usually around a more massive body.''

If something's not in orbit around something, it isn't meaningful to talk about orbital velocity for it.

 

[Crisium]

re: HSC Physics Marathon Archive

Soz if this sounds super dumb but can u calculate orbital velocity for things that aren't in orbit?

If you relate it to the formula it's independent of the mass of the object orbiting but dependent on the mass of the planet/celestial body

Are you thinking about calculating the speed of an electron as it is deflected by an electric field and curves out a path (that's the closest thing I can picture to what you mean by it not being in an orbit)?

 

[astroman]

re: HSC Physics Marathon Archive

I was wondering if you could apply it to gliders.

 

[atargainz]

re: HSC Physics Marathon Archive

 

[turntaker]

re: HSC Physics Marathon Archive

View attachment 32588

Never seen a question like that.
Someone tell plz

 

[astroman]

re: HSC Physics Marathon Archive

Never seen a question like that.
Someone tell plz

 

[Crisium]

re: HSC Physics Marathon Archive

I think markers like to see a mention of the "standing wave", "nodes" and "anti-nodes" to determine the wavelength AND with the known frequency and using the wave equation (v = f (lambda) ) he could calculate the speed of radio waves which of course closely aligned to that of the known speed of light suggesting that an electromagnetic spectrum did in fact exist

 

[astroman]

re: HSC Physics Marathon Archive

For ways on minimising g-forces can we talk about breathing patterns, tensing your body to minimise blood loss from the brain and stuff like that??

 

[Mr_Kap]

re: HSC Physics Marathon Archive

I think markers like to see a mention of the "standing wave", "nodes" and "anti-nodes" to determine the wavelength AND with the known frequency and using the wave equation (v = f (lambda) ) he could calculate the speed of radio waves which of course closely aligned to that of the known speed of light suggesting that an electromagnetic spectrum did in fact exist

Nah doubt it. My teacher just said to say that he "measured" the wavelength an he KNEW the frequency, so he could v = f (lamda) the wave.

 

[Mr_Kap]

re: HSC Physics Marathon Archive

For ways on minimising g-forces can we talk about breathing patterns, tensing your body to minimise blood loss from the brain and stuff like that??

no idea.n I doubt it. This is physics not biology.


can someone also answer: "How can we ensure the safety of astronauts from G-forces"

 

[Crisium]

re: HSC Physics Marathon Archive

Nah doubt it. My teacher just said to say that he "measured" the wavelength an he KNEW the frequency, so he could v = f (lamda) the wave.

If you instil that much hope in your teacher then by all means leave that as your answer

 

[astroman]

re: HSC Physics Marathon Archive

no idea.n I doubt it. This is physics not biology.


can someone also answer: "How can we ensure the safety of astronauts from G-forces"

lie down horizonal instead of sitting up so eyeballs dont pop out, improves circulation, seat is usually made of memory foam to contour to the body
wear a g suit
wear an oxygen mask to keep oxygen flowing for the brain to prevent blacking out
slowly accelerate and have correct angles for reentry

 

[Crisium]

re: HSC Physics Marathon Archive

For ways on minimising g-forces can we talk about breathing patterns, tensing your body to minimise blood loss from the brain and stuff like that??

Just talk about the person's posture and the chair made of fibreglass they lay on (It's specifically shaped to their body so that the g-forces are evenly spread through the body)

+ Talk about how the eye balls in approach is easier to tolerate than the eye balls out approach

+ If possible (depending on the situation) throttling the thrust

+ If you want to talk about physiological processes then refer to the symptoms of black out and/or red out

 

[atargainz]

re: HSC Physics Marathon Archive

no idea.n I doubt it. This is physics not biology.


can someone also answer: "How can we ensure the safety of astronauts from G-forces"

G-forces should be restricted to 3g if possible, 8g max (causes chest pain and loss of consciousness)
- Transverse application of g load is easiest to cope with, meaning astronauts should be lying down at take-off, not standing or sitting vertically, this will prevent blood from being forced away from the brain
- ‘Eyeballs-in’ application of g loads easier to tolerate than ‘eyeballs-out’ – astronauts should lift-off forwards (facing up) but re-enter backward (facing up)
- Supporting body in as many places as possible – contoured couch, built of fibreglass & moulded to suit the body of a specific astronaut settled on – using this can be subjected to loads of up to 20 g

 

[astroman]

re: HSC Physics Marathon Archive

G-forces should be restricted to 3g if possible, 8g max (causes chest pain and loss of consciousness)
- Transverse application of g load is easiest to cope with, meaning astronauts should be lying down at take-off, not standing or sitting vertically, this will prevent blood from being forced away from the brain
- ‘Eyeballs-in’ application of g loads easier to tolerate than ‘eyeballs-out’ – astronauts should lift-off forwards (facing up) but re-enter backward (facing up)
- Supporting body in as many places as possible – contoured couch, built of fibreglass & moulded to suit the body of a specific astronaut settled on – using this can be subjected to loads of up to 20 g

fibreglass or memory foam or both?

 

[astroman]

re: HSC Physics Marathon Archive

Q (2002 JR Trial) : In an induction motor, discuss why it is important to have an electromagnet as opposed to a permanent magnet creating the magnetic field and how this magnetic field causes rotation.

 

[Crisium]

re: HSC Physics Marathon Archive

fibreglass or memory foam or both?

fibreglass

I've never heard of memory foam before

But it sounds familiar though (you see what I did there )

 

[astroman]

re: HSC Physics Marathon Archive

fibreglass

I've never heard of memory foam before

But it sounds familiar though (you see what I did there )