2013 study design?

[CatMeoooow]

Howdy

In the new study design, for unit 4, it states apply a vector field model to magnetic phenomena including shapes and directions of fields produced by bar magnets, current carrying wires, coils, and solenoids.

In the old design instead of vector field model it was just field model.

Can someone please explain the difference of vector field model and field model?

Thanks

[Lasercookie]

In terms of what you'll be doing in VCE Physics (magnetic fields), it's the same thing, just VCAA being a bit more precise with their terminology. You do have scalar and vector fields, but a magnetic field is a vector field, since it has an associated magnitude and direction at each point.

[CatMeoooow]

This isn't relevant but can you tell me if this is correct.   

For    R=V/I     

If the current increases does the resistance decrease?

[Jenny_2108]

This isn't relevant but can you tell me if this is correct.   

For    R=V/I     

If the current increases does the resistance decrease?

yep

[pi]

If the current increases does the resistance decrease?

Only if the Voltage is constant. May seem very picky, but you need to mention that in an exam response.

[Jenny_2108]

If the current increases does the resistance decrease?

Only if the Voltage is constant. May seem very picky, but you need to mention that in an exam response.

LOL, do you have to mention that its an electrical circuit in the exam as well?
I think the question already implies its constant voltage. Unless the change isnt comparable

[pi]

LOL, do you have to mention that its an electrical circuit in the exam as well?
I think the question already implies its constant voltage. Unless the change isnt comparable

No, that's just stupid, Ohm's Law isn't used on a cucumber.

I said it was being picky, but it's all about making sure you get 1/1 from both examiners and not cutting corners and skipping details to risk losing 0.5 or even 1 mark when it comes to collation. The statement is ONLY true if V is constant, and it takes ~5 seconds to add that line.

[Aurelian]

I don't think it's being picky at all, I think it's quite necessary to explicitly say that voltage must be taken as constant for it to be true.

I mean, seriously, in every day life currents are generally altered by varying voltage anyway, not resistance...

[paulsterio]

LOL, do you have to mention that its an electrical circuit in the exam as well?
I think the question already implies its constant voltage. Unless the change isnt comparable

No, the question does not imply that it is a constant voltage.

For example, when you do electric power, you'll see that there are essentially two ways to reduce power loss, reducing the transmission current or reducing the resistance of the wires (both are independent processes). Guess what, reducing transmission current is done by increasing the voltage (that's why we use step-up transformers).

Thus, in many ways, I could easily argue that if I change the voltage, the current, not the resistance, will change. Hence, you have to explicitly mention that the voltage is constant.

[Jenny_2108]

LOL, do you have to mention that its an electrical circuit in the exam as well?
I think the question already implies its constant voltage. Unless the change isnt comparable

No, the question does not imply that it is a constant voltage.

For example, when you do electric power, you'll see that there are essentially two ways to reduce power loss, reducing the transmission current or reducing the resistance of the wires (both are independent processes). Guess what, reducing transmission current is done by increasing the voltage (that's why we use step-up transformers).

Thus, in many ways, I could easily argue that if I change the voltage, the current, not the resistance, will change. Hence, you have to explicitly mention that the voltage is constant.

I just saw R=V/I and simply thought R and I are inversely proportional so if I increases, R decreases

Anyway, I dont do Physics though. All of you are correct