Was that a Maths exam? (2 Viewers)

TechnIx

Member
Joined
Apr 4, 2009
Messages
88
Gender
Male
HSC
N/A
Or use S=ut+1/2at^2 and use S=0.

or use t=2usinθ / g and use g as the accel.
Hey I might have actually gotten that question right (against all odds!)

I thought I was way off, but I remember using that equation and making S=0.

Then I got two answers for t
t=0 and t=something else

So yeah, sweet....
 

sinophile2

Member
Joined
Sep 26, 2009
Messages
135
Gender
Undisclosed
HSC
N/A
Sweet, there was plenty of nice maths in that exam. Im surprised.

I was going a bit nuancy with the electron defleciton question. Considered that the repulsive force would vary inversely with the distance of the electron from the plate, so that its downard acceleration would be variable. IN hindsight, it was an electric field and not a magnetic one so it should've been linear.
 

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
Considered that the repulsive force would vary inversely with the distance of the electron from the plate, so that its downard acceleration would be variable. IN hindsight, it was an electric field and not a magnetic one so it should've been linear.
In an electric field the force experienced by the same charges are constant if the field is uniform.
 

sinophile2

Member
Joined
Sep 26, 2009
Messages
135
Gender
Undisclosed
HSC
N/A
I stated that the acceleration due to gravity on the electron is negligible. In addition to this, they did not provide the orientation of the apparatus so you cannot know the direction of the gravity. You'll either have to make one assumption (that gravity is 'down the page') or another (there is no gravity).
 

jonjoony

Member
Joined
Nov 9, 2008
Messages
56
Gender
Male
HSC
2010
Finished it in 1hr exactly :) walked off everyone was like wtf? Ugly ass test imagine not bringing a calculator to tha tone lol
 

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
Finished it in 1hr exactly :) walked off everyone was like wtf? Ugly ass test imagine not bringing a calculator to tha tone lol
I didn't use a calculator in the exam, I never do for Physics especially since the angle given was 60 deg in the projectile.

And that's stupid walking off after 1 hour... You will have made so many mistakes.
 

random-1005

Banned
Joined
Dec 15, 2008
Messages
609
Gender
Male
HSC
2009
I didn't use a calculator in the exam, I never do for Physics especially since the angle given was 60 deg in the projectile.

And that's stupid walking off after 1 hour... You will have made so many mistakes.
oi fuk stick, how did you do the kelpers law question then, can you multiply fukin massive numbers in your head, you knob
 

kaz1

et tu
Joined
Mar 6, 2007
Messages
6,960
Location
Vespucci Beach
Gender
Undisclosed
HSC
2009
Uni Grad
2018
I didn't use a calculator in the exam, I never do for Physics especially since the angle given was 60 deg in the projectile.
I find that very hard to believe. How do you do the relativity ones with the square roots and the ones with massive numbers and you don't really give exact answers in Physics.
 

Aerath

Retired
Joined
May 10, 2007
Messages
10,169
Gender
Undisclosed
HSC
N/A
I didn't use a calculator in the exam, I never do for Physics especially since the angle given was 60 deg in the projectile.
LOL, that's total bullshit. Even if the angle was 60 degrees, it was times by 1.6x10^16 m/s or some crap.
 

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
oi fuk stick, how did you do the kelpers law question then, can you multiply fukin massive numbers in your head, you knob
It's not as hard as you make it out to be. Problem with most people is that they've become too calculator dependent, which in itself isn't that bad, but I just don't want to fall into that category :) And I make stupid mistakes on a calculator sometimes, which is eliminated if I don't use one.

I find that very hard to believe. How do you do the relativity ones with the square roots and the ones with massive numbers and you don't really give exact answers in Physics.
I give my answer to 1 sig fig most of time (sometimes to 2 sig fig, if I am certain that it is correct)... and I can do most square roots correct to 1 d.p. And plus, in Physics at HSC level you can be 1 decimal place off and still get the marks, unlike Maths, given that you've shown all working.

LOL, that's total bullshit. Even if the angle was 60 degrees, it was times by 1.6x10^16 m/s or some crap.
Again, it's not as hard as you make it out to be. You've probably been using a calculator all your HSC so you probably are not used to it. The only time I use a calculator in Physics is for irregular angles (ie. not 30, 60 or 45 deg). I just remember that sin60 deg = 0.866 to 3 d.p etc. Works most of the time :)
 

untouchablecuz

Active Member
Joined
Mar 25, 2008
Messages
1,693
Gender
Male
HSC
2009
It's not as hard as you make it out to be. Problem with most people is that they've become too calculator dependent, which in itself isn't that bad, but I just don't want to fall into that category :) And I make stupid mistakes on a calculator sometimes, which is eliminated if I don't use one.


I give my answer to 1 sig fig most of time (sometimes to 2 sig fig, if I am certain that it is correct)... and I can do most square roots correct to 1 d.p. And plus, in Physics at HSC level you can be 1 decimal place off and still get the marks, unlike Maths, given that you've shown all working.


Again, it's not as hard as you make it out to be. You've probably been using a calculator all your HSC so you probably are not used to it. The only time I use a calculator in Physics is for irregular angles (ie. not 30, 60 or 45 deg). I just remember that sin60 deg = 0.866 to 3 d.p etc. Works most of the time :)
Kim Peek - Wikipedia, the free encyclopedia
 

addikaye03

The A-Team
Joined
Nov 16, 2006
Messages
1,267
Location
Albury-Wodonga, NSW
Gender
Male
HSC
2008
Same here. SWEET. I like the high level of maths in the physics. It makes you think and apply different equations.
o_O, do you mean that as in the number of maths Q compared to theory or the difficulty of the maths?

If the latter, i wouldn't take Uni Physics if i was you
 

random-1005

Banned
Joined
Dec 15, 2008
Messages
609
Gender
Male
HSC
2009
That was uncalled for.
i think its pretty appropriate, lol, you make mistakes when you use a calculator, so to minimise this you have decided to memorise every square root and multiplication ever, you tard, you cnt even use a calculator

bloody tosser, think you are hot shit coming on here saying you did the physics test without a calculator
 
Last edited:

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
i think its pretty appropriate, lol, you make mistakes when you use a calculator, so to minimise this you have decided to memorise every square root and multiplication ever, you tard, you cnt even use a calculator
It's not that hard... For example, for \sqrt(69) you know that \sqrt(64) = 8, and \sqrt(81)=9... So \sqrt(69) is going to be more near 8 than 9... So it's about 8.
 

biopia

WestSyd-UNSW3x/week
Joined
Nov 12, 2008
Messages
341
Gender
Male
HSC
2009
It's not that hard... For example, for \sqrt(69) you know that \sqrt(64) = 8, and \sqrt(81)=9... So \sqrt(69) is going to be more near 8 than 9... So it's about 8.
Lol! You can't estimate like that! I am sure that would account for more than one decimal place of error!

Did your teacher condone this lol?

:S
 

addikaye03

The A-Team
Joined
Nov 16, 2006
Messages
1,267
Location
Albury-Wodonga, NSW
Gender
Male
HSC
2008

Aerath

Retired
Joined
May 10, 2007
Messages
10,169
Gender
Undisclosed
HSC
N/A
It's not as hard as you make it out to be. Problem with most people is that they've become too calculator dependent, which in itself isn't that bad, but I just don't want to fall into that category :) And I make stupid mistakes on a calculator sometimes, which is eliminated if I don't use one.


I give my answer to 1 sig fig most of time (sometimes to 2 sig fig, if I am certain that it is correct)... and I can do most square roots correct to 1 d.p. And plus, in Physics at HSC level you can be 1 decimal place off and still get the marks, unlike Maths, given that you've shown all working.


Again, it's not as hard as you make it out to be. You've probably been using a calculator all your HSC so you probably are not used to it. The only time I use a calculator in Physics is for irregular angles (ie. not 30, 60 or 45 deg). I just remember that sin60 deg = 0.866 to 3 d.p etc. Works most of the time :)
Yeah, I doubt too many people could do 0.866 x 1.6x10^16 in their heads. Nor would you be able to do the electron motion question. Nor Kepler's Third Law.

Too bad I reckon you're just trolling around for attention.
 

Tofuu

Member
Joined
Jul 31, 2008
Messages
319
Gender
Undisclosed
HSC
2010
this is making me regret not picking physics, sigh, if only i knew it was a whole lot of math
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top