Multiple Choice (3 Viewers)

[RealiseNothing]

Fairly sure 17 is D, so you will probably get 19/20.

 

[spongebob1]

14 is c? V= Ed where V is constant? Isnt that a linear relationship so a straight line

 

[Menomaths]

1) b
2) d
3) a
4) a
5) d
6) c
7) a
8) d
9) b
10) c
11) b
12) a
13) d
14) b
15) a
16) d
17) b
18) c
19) c
20) b

Tossing up between 17 b or d.. probably determines my 19/20 or 20/20

Sadly 17 is not b

 

[Randox]

14 is c? V= Ed where V is constant? Isnt that a linear relationship so a straight line

I put c. That was my thinking behind it

 

[RealiseNothing]

14 is c? V= Ed where V is constant? Isnt that a linear relationship so a straight line

E=V/d

 

[MATHmaster]

14 is c? V= Ed where V is constant? Isnt that a linear relationship so a straight line

That's a hyperbola

 

[spongebob1]

Yeh rearrange it for v and v is a constant?

 

[spongebob1]

V=Ed isnt a hyperbola...

 

[spongebob1]

That's a hyperbola

cmon math master even randox knows whatsup

 

[MATHmaster]

E = V/d
You're graphing E on the y-axis and d on the x-axis
let E = y and d = x
Hence y = V/x where V is constant
Therefore it is a hyperbola

 

[anomalousdecay]

E = V/d
You're graphing E on the y-axis and d on the x-axis
let E = y and d = x
Hence y = V/x where V is constant
Therefore it is a hyperbola

You're right. It is a hyperbola. Listen to 4-unit not 2-unit.

 

[Web Addict]

14/20 and stuffed up the photocell. Band 5 is gonna be a mission now.

Feel so bad after getting a 19/20 in Chemistry.

I know that feeling.

 

[anomalousdecay]

I know that feeling.

And Chem is suppossed to be harder.

I'm gonna say this now, might be too early:

"I'm gonna miss Chemistry in uni"

HSC Chemistry is so much more enlightening than the philosophy of HSC Physics.
At least engineering uni physics is nothing like HSC.

 

[Hoskiies]

1) b
2) d
3) d
4) a
5) d
6) c
7) a
8) d
9) b
10) c
11) b
12) a
13) b
14) b
15) a
16) c
17) c - Not sure, because the X axis says motor speed not time, So as motor speed increases shouldn't torque also increase?
18) c
19) c
20) b

 

[yasminee96]

And Chem is suppossed to be harder.

I'm gonna say this now, might be too early:

"I'm gonna miss Chemistry in uni"

HSC Chemistry is so much more enlightening than the philosophy of HSC Physics.
At least engineering uni physics is nothing like HSC.

I made this really stupid decision to drop chemistry and keep physics.
kml

 

[uart]

1) b
2) d
3) a
4) a
5) d
6) c
7) a
8) d
9) b
10) c
11) b
12) a
13) d
14) b
15) a
16) d
17) b *Controversial
18) c
19) c
20) a * Should be "b"

Good work RN, all correct there except for 20. Answer for 20 is b.

Reason why 20 is b: The frequency of the light is c/lambda = 6.7E14, so *only* metal "X" is illuminated above the threshold for electron emission, so the number of emitted electrons increases only in metal "X". The number of electrons emitted from metal "Y" will remain zero both before and after the increase in intensity.

Note that Q17 is controversial. The answer to 17 could be either "b" or "d" depending on what assumptions are made. See my post below.

 

[Menomaths]

Good work RN, all correct there except for 20. Answer for 20 is b.

Reason why 20 is b. The frequency of the light is c/lambda = 6.7E14, so only metal "X" is illuminated above the threshold for electron emission. So the number of electron increase in metal "X" only, the electrons emitted from metal "Y" will remain zero both before and after the increase in intensity.

There's one more wrong answer in there.

 

[anomalousdecay]

I made this really stupid decision to drop chemistry and keep physics.
kml

I don't know. Hope that I can somehow integrate chemistry into electrical.
It only looks good in terms of pv cells and materials used and batteries. Worst compromise of wanting to do chemical and electrical at the same time.

And you probably would have benefited more with chem for med.

 

[uart]

There's one more wrong answer in there.

Are you referring to Q17, I was just about to discuss that. That question is controversial in my opinion.

The answer for 17 is b if motor is supplied by constant current, but is d if the motor is supplied by a constant voltage source.

The question didn't specify whether the voltage was constant or if the current was constant in this case, so it's quite ambiguous. I agree that constant voltage sources are more commonly used than constant current, so it could be argued that "d" is *more* correct than "b". To be honest though, it's hard to know for sure what assumption they were expecting the students to make here and how they will mark that one.

 

[Menomaths]

Are you referring to Q17, I was just about to discuss that. That question is controversial in my opinion.

The answer for 17 is b if motor is supplied by constant current, but is d if the motor is supplied by a constant voltage source.

The answer is what Fizzy said