Going thorugh the Syllabus: SPACE (1 Viewer)

[allyteaded]

Mathematician suggested this. I thought it was a good idea. Rahul suggested to start a new thread so I did.

Join in if you're game. We'll start with one dot point and everyone who has an answer can post. It's good for you! Testing your knowledge. If you're slightly wrong or have missed something, someone can correct you. Better now than in the HSC!

... then once dotpoint seems to be covered, someone can start the next dot point with a related question.

In the end we'll have notes made by everyone. That way, when you're answering questions / studying on your own you can refer to these notes and see if you've missed anything out.

I'll need people to help me and co-operate - I'm only starting this because I think it might be a good way to study. I don't want to take charge or anything.

For the first question (I'm sticking two at a time because they're pretty easy):


1. Define the term "weight."

2. What is meant by "gravitational potential energy?"


Anyone game enough to answer?

 

[Dave85]

1) weight is the force acting on an object due to a gravitational field. Its a vector quantity and measured in newtons. W=mg where g is the acceleration due to gravity measured in m/s2.

2) the amount of energy it takes to move an object from a very large distance to a point in a gravitational field

 

[Ragerunner]

gravitational potential energy just a more expanded word for the work done

 

[dandaman]

perform an investigation to help distinguish between non-inertial and inertial frames of reference???

i saw something somewhere about using an accelerometer... wouldnt have a clue how.. can someone explain this?

 

[Ragerunner]

huh?

I've never seen this dot point before?

Then again, i missed out on the westinghouse one.

I need an explanation of it as well

 

[Dash]

Originally posted by dandaman
perform an investigation to help distinguish between non-inertial and inertial frames of reference???

i saw something somewhere about using an accelerometer... wouldnt have a clue how.. can someone explain this?

Well, all I can say to that is: Non-Inertial frames of references are those that are accelerating and intertial frames of references are in travelling at a constant velocity. So a simple experiment that would reveal if you were in either of the two frames of references would be to chuck a ball up into the air. If lets say you project it vertically upwards (perfectly ), the ball will fall straight back down if you were in a intertial frame of reference, however, if it were to follow a slighty parabolic path in the opposite direction of the acceleration, you would deduce that you were in an non-intertial frame of reference.

 

[Dash]

This one is a weird one for me. Maybe its just that I can't be bothered, but can someone help me with this one?

Analyse information to discuss the relationship between theory and the evidence supporting it, using Einstein's predictions based on relativity that were made many years before evidence was available to support it.

 

[dandaman]

without the michelson morely experiment then einstein's claims may not have been acknowledged??

i think thats wot theyre on about

 

[Dave85]

i HATE the dot point. ALl i know is that eistien put forward his thories regarding special relativity and its only been in recent times that there has been evidence to support. E.g. two atomic clocks are used. One in a superfast jet and the other on the ground. The jet flew for a 24 hr period and when it landed there was a slight different in time between the 2 clocks as time slowed down on the super fast jet. ALso particle accelerators hav showed the mass of objects increase as they approach the speed of light. I can tell you that much but i dont get the 'relationship between thory and evidence' bit. I gueesss there relationship is that the evidence supports the thoery but took many years until it cud support it. SOrry if thats useless

 

[sammie]

With the Westinghouse and Edison point, it took me ages to find stuff but i think like in short points Edison was interested in DC and Westinghouse AC. You then get to see when you get information how both try to get power to larger cities etc and problems they in-counted. Westinghouse actually did not invent things he bought them off others . For example he brought the idea of the transformer so that he could mass supply electricty .
i don't know if this right but might put you on the right track.

 

[Dash]

Originally posted by Dave85
i HATE the dot point. ALl i know is that eistien put forward his thories regarding special relativity and its only been in recent times that there has been evidence to support. E.g. two atomic clocks are used. One in a superfast jet and the other on the ground. The jet flew for a 24 hr period and when it landed there was a slight different in time between the 2 clocks as time slowed down on the super fast jet. ALso particle accelerators hav showed the mass of objects increase as they approach the speed of light. I can tell you that much but i dont get the 'relationship between thory and evidence' bit. I gueesss there relationship is that the evidence supports the thoery but took many years until it cud support it. SOrry if thats useless

Yeh, I kind of get what your talking about. We just basically have to show how Einstein's perdictions are now able to be supported by experimental evidence. Gotcha!

Originally posted by sammie
With the Westinghouse and Edison point, it took me ages to find stuff but i think like in short points Edison was interested in DC and Westinghouse AC. You then get to see when you get information how both try to get power to larger cities etc and problems they in-counted. Westinghouse actually did not invent things he bought them off others . For example he brought the idea of the transformer so that he could mass supply electricty .
i don't know if this right but might put you on the right track.

Wouldn't Edison be fucked... Cos I don't think you can transfer DC currents to customers as effectively as AC can using transformers

 

[SmokedSalmon]

The NSW HSC online website: http://hsc.csu.edu.au/
has an update for the physics dot points. It has an entire answer to Westinghouse and Edison if you are wanting one.
Btw Isn't an Inertial Frame of Reference is where the object is also at rest and not only when it is travelling at constant velocity? Bah... I'm sure u knew that Dash just forgot to mention it.