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Was that a Maths exam? (3 Viewers)

TechnIx

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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

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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

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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

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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

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Finished it in 1hr exactly :) walked off everyone was like wtf? Ugly ass test imagine not bringing a calculator to tha tone lol
 

cutemouse

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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

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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

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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

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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

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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

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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

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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

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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
 
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cutemouse

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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

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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

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Aerath

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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

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this is making me regret not picking physics, sigh, if only i knew it was a whole lot of math
 

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