27 Wtf (2 Viewers)

[himiniji]

Did anyone else get 8 ohms as the resistence?

 

[dolbinau]

I put 7.5

 

[alez]

i put 5.6. figured they would have put the resistance in there to catch some people
and the resistor was before the wire and voltmeter
took a guess

 

[runnable]

We were supposed to subtract 2 ohms from whatever we got for our inverse of the gradient (resistance).. Damn..

 

[dolbinau]

Oh yeah, I think that must be right. I changed my answer from that too. Ok 4 marks gone from question 27 now, LOL. God that's horrible.

 

[alez]

lol i fucked up the last bit. with the explanation for the dodgy value
couldnt think of anything. made up the biggest load of shit

 

[dwarven]

lol dude
nothing you can do to change it now.
just dw about it and focus on ur next one.

 

[frogbutt]

oooh that reminds me. the very last part of q 27. Why is one of the points off the line. I put because the wire is not a perfect ohmic conductor and therefore wont conform perfectly to v=IR. thoughts?

no they were ohmic conductors because they passed through the origin and were linear.

it was just an outlier because at the higher voltage, heat caused the resistance to increase and so the current was a bit less.

 

[cookiemonsterz]

What is this about subtracting 2 ohms???
what i did...

drew the graph.
found the inverse of the gradient, 7.5 ohms.
wire x was pure because it had a larger gradient and thus smaller resistance.
because it is not perfectly ohmic, it was ohmic untill the voltage got to a certain level, the fact that "heat caused the resistance to increase and so the current was a bit less" is actually evidence of this.

 

[dolbinau]

lol dude
nothing you can do to change it now.
just dw about it and focus on ur next one.

No more. It's all over (exam wise). I do need to get over it though, hehe.

What is this about subtracting 2 ohms???

Diagram of circuit had 2 ohm resistor.

 

[duy.le]

lol yeh im pretty sure i got that wrong, i changed my asnwer from that to 'the ammeter goes up to 2.50 only' LMAO i cant stop laughing at how stoopid my asnwer was, oh well, it fit pretty well at the time ----> 1 mark

and did we have to subtract 2 ohms from our answers (ie inverso fo the gradient of graph) caus ethere was a 2 ohm resistor in teh circuit??

HOLY SHIT MAYB

 

[dwarven]

No more. It's all over (exam wise). I do need to get over it though, hehe.

same here

nothing to do now tho :S

 

[karnage]

fuck you 2 ohms

 

[Aaron.Judd]

You got 2 marks if you plotted the points and drew a line of best fit correctly. Some peopel I know missed it.

 

[Aaron.Judd]

I got r = 7.5. Never thoguht about the resistor in the circuit.

 

[pdoueihi]

Was that just part of the 2 mark question about which one is pure, Alez?

2 marks to find resistance, 2 marks for Pure one, 1 mark for Outlier - It's out of 6. What am I missing?

what u put for outlier? i put that the current was on too long and heated up to higher resistance. right or wrong?

 

[Chrisssss]

Looks like hardly anyone thought of the resistor (I didn't either)
And was I the only one who simply said regarding the outlier that a probable cause was human error? I just said that human error could cause the outlier due to inaccurate reading or what not. I really didn't know what the hell I was doing with that Q though.

 

[dolbinau]

Looks like hardly anyone thought of the resistor (I didn't either)
And was I the only one who simply said regarding the outlier that a probable cause was human error? I just said that human error could cause the outlier due to inaccurate reading or what not. I really didn't know what the hell I was doing with that Q though.

I said human error too. And yeah this question, LOL, God. It's like year 11 work (almost) and I got 4 marks wrong!!

 

[independantz]

You got 2 marks if you plotted the points and drew a line of best fit correctly. Some peopel I know missed it.

Wtf? I never saw this Q.

 

[Aaron.Judd]

Wtf? I never saw this Q.

It was right at the top. It sort of just looked like they were explaining it, but you defiantly got 2 marks to plot the graph/trend line it.