Projectile Vertical Motion

[Yoda]

Hello 

Can someone please explain vertical motion and what formulas to use to find the veritcal motion?

Thankyah mang

[Jenny_2108]

Hello 

Can someone please explain vertical motion and what formulas to use to find the veritcal motion?

Thankyah mang

Vertical motion is one dimensional motion along a straight line of force

Normally we mention about vertical motion under gravity (constant acceleration g)

Formula: 

P/S: I don't do Physics though, its just from Spesh

[abeybaby]

s=vt-1/2at^2, dont forget that one!

[Jenny_2108]

s=vt-1/2at^2, dont forget that one!

its not in the formula sheet. Can we use it directly in the exam?

[Bhootnike]

s=vt-1/2at^2, dont forget that one!

its not in the formula sheet. Can we use it directly in the exam?

yes, its pretty much the same as the x= ut + 1/2at^2
except its using final veocity

[Jenny_2108]

s=vt-1/2at^2, dont forget that one!

its not in the formula sheet. Can we use it directly in the exam?

yes, its pretty much the same as the x= ut + 1/2at^2
except its using final veocity

final and initial velocity are totally different. I'm unsure if we can use it without proving

[Bhootnike]

i didnt say they were the same haha
and no, you dont have to prove it.
its fine! 
im sure lovephysics would love to share his thoughts on proving things in vce physics here btw :p

[Jenny_2108]

i didnt say they were the same haha
and no, you dont have to prove it.
its fine! 
im sure lovephysics would love to share his thoughts on proving things in vce physics here btw :p

LOLLLLLLLL

[abeybaby]

its not on the formula sheet :O

[Bhootnike]

its not on the formula sheet :O

i dont think it matters.
theres a few other formulas that arent on the formula sheet we use, e.g.

[Aurelian]

Whether or not a formula is on the formula sheet has literally no bearing on whether you can use it lol

[Jenny_2108]

^ Well you can prove it though but I mean I haven't seen it in the textbook or study guide whatever (or is it used in Physics?) so not sure whether you can use in the exam

Like you can't apply method of spesh into maths methods because the formula isn't in the course (you can but people said you might not get full mark for it)

[Bhootnike]

Like you can't apply method of spesh into maths methods because the formula isn't in the course (you can but people said you might not get full mark for it)

It says on vcaa im pretty sure that you get full marks still
i think you just need to justify, e.g. if you use second derivatives..! which you should do regardless of whether its spesh or methods

but yeah, theres many formulas in physics which we use that arent on the formula sheet.
tsfx gives out all these extra ones too which they say to use!

[paulsterio]

Jenny, there's no reason why you can't use it, given that it's pretty much "derived" by common definitions.





Now just add them:





Which is a common formula. There you go, it's not hard to derive and if you think about it, it's common sense because what you "add" to the initial velocity is what you "subtract" from the final velocity, if that makes sense.

final and initial velocity are totally different. I'm unsure if we can use it without proving

Not really, they're not "totally different" - remember that we are talking about rectilinear motion with constant acceleration, meaning that the final velocity is dependent upon the initial velocity. So they are related.

And lastly, Jenny, Physics is completely different to maths - in Physics, you're allowed to (and some would even say encouraged to) take shortcuts and use quick formulas, because marks are awarded for the correct answer in the box, i.e. if you get a correct answer in the box, you will be awarded full marks, regardless of your working.

[Jenny_2108]

^ I promise I'll never ever go to Physics board again