Physics Derivations

chicken_food

Any clues as to which one they might ask.
Im thinking newtowns law one.

nobodythere

I'm thinking that too, but it's fairly easy. Cover your ass with the F=qvb and the Kepler proof

Doctor D-Man

ya definitely F=ma being a special case of newtons second law of motion.

also know derivation of period of a sattelite

How many derivations are actually required. There isnt that many is there. Resistors in series and parallel might also come up but theyre too easy.

anything else...?

chicken_food

Usually they only ask one per exam and there are 6 ones that you are told to know. 3 of which are the v=u+at etc etc.

JackKelly

newtons second law derivation.......um...which ones that?

Africa

what derivations do we know...for claritys sake...like i know them...but not actually. Get me? No?

Ah well. I tried.

chicken_food

no proportional button so equals sign means proportional to

F = (mv-mu)/t
f = m(v-u/t)
f = m a
f=(equals) kma

JackKelly

hmmm. Must have missed that one. Looks easy enough. Nice one.

chicken_food

Mechanincs 1 Page 16 (m.16) shes a beaut!

stevoxbx

I didnt know we had to be able to derive any formula so ****ed for tomorrow

Richard_Fonzie

v=u+at
s=ut+1/2ft^2
v^2=u^2+2as
f=ma
f=qvb

What's the sixth one?

OTliddy

Richard_Fonzie wrote:

v=u+at
s=ut+1/2ft^2
v^2=u^2+2as
f=ma
f=qvb

What's the sixth one?

Keplar's 3rd law

exiztone

Richard_Fonzie wrote:

v=u+at
s=ut+1/2ft^2
v^2=u^2+2as
f=ma
f=qvb

What's the sixth one?

Period of an orbit is kind of one.

Webmonkey

Well yeah thats keplars third law. T² = 4Л²l/g (sketchy looking pie)

Richard_Fonzie

T² = 4Л²l/g (sketchy looking pie)

That's Kepler's third law? I thought that was period of SHM of a pendulum.
Isnt it T² = 4Л²R³/GM

Richard_Fonzie

Richard_Fonzie wrote:

That's Kepler's third law? I thought that was period of SHM of a pendulum.
Isnt it T² = 4Л²R³/GM

Yeah that's it alright.

Webmonkey

**** sorry i am all confused. But the orbit is keplars law still

Vikings

All the talk from honours physics is hurting my head! Stop it already im trying to relax before my last exam.

sixdraw

HERE THE PERIOD ONE IS FINE.
all's you need is :
1)the time taken to travel a circle is 2(pi)(r)/velocity = T
2)then combine mv^2/r and Gm1m2/r^2 . and get V equals
3)put that into 2(pi)(r)/v

sci0x

And this is the one that came up! Lucky I had looked over it the night before.