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Noodles is gay
05-18-2005, 02:36 PM
A tennis player is standing 5.5m from the net. She hits the ball horizontally at a speed of 32m/s. How far has the ball dropped when it reaches the net? Take g = 10m/s/s.

Can anybody work that out? And tell me how to do it please? I have been trying for almost an hour now, i've gone through a ridiculous amount of paper and still have nothing! :mad: It's really simple and i must be missing something because otherwise i would have it but no!

so yeah, dammit, where is Endymion when i need him?

the_GoDdEsS
05-18-2005, 02:38 PM
Heh, I kinda hated those. *huggles Jenny*

Noodles is gay
05-18-2005, 02:41 PM
I KNOW it's basic which is why i'm so pissed off with the bloody thing! I would normally have it by now and be dancing and laughing but no, not today. It just won't work - it refuses to work for me.

cheers goddess, i hate this part of physics too :mad:

Sinister
05-18-2005, 02:49 PM
I'd help but I'm kinda too stupid. actually I just haven't learned that kind of shit yet. but anyway.

*gives NIG a mug of coffee* there you go, you're gonna be able to stay up all nite working on it.

Noodles is gay
05-18-2005, 02:55 PM
YES! Coffee! now that's a plan.

Well i'll leave this thread here and hopefully some kind soul will solve it and post how they did it later. *crosses fingers* I'm off for coffee and further destroying of the rainforest trying to solve this damnable easy question.

Brines
05-18-2005, 02:56 PM
I did it in 7th grade, but I forgot.

Sinister
05-18-2005, 03:00 PM
YES! Coffee! now that's a plan.

Well i'll leave this thread here and hopefully some kind soul will solve it and post how they did it later. *crosses fingers* I'm off for coffee and further destroying of the rainforest trying to solve this damnable easy question.

use your comp - wordpad, calculator... that way you're gonna save some trees.

*gives you another mug*

darko
05-18-2005, 03:00 PM
if your that stuck, leave it for a while....clear your head, then go back to it....i cant remember who to do those...

LordOfdEAthAndTime
05-18-2005, 03:02 PM
A tennis player is standing 5.5m from the net. She hits the ball horizontally at a speed of 32m/s. How far has the ball dropped when it reaches the net? Take g = 10m/s/s.

Can anybody work that out? And tell me how to do it please? I have been trying for almost an hour now, i've gone through a ridiculous amount of paper and still have nothing! :mad: It's really simple and i must be missing something because otherwise i would have it but no!

so yeah, dammit, where is Endymion when i need him?


I know how to do it!!! ME ME ME!!! easy you have to get the 5.5m and the 32m/s and multiply it then divide it by G-10 m/s/s and you get your answer!

Mota Boy
05-18-2005, 03:04 PM
I'm not going to bother working it out, but calculate the time that it takes for the ball to reach the net (5.5/32) then treat it as if the ball had been in free fall for that amount of time.

Noodles is gay
05-18-2005, 03:46 PM
^ 0.17, and then i do what? :confused:


I know how to do it!!! ME ME ME!!! easy you have to get the 5.5m and the 32m/s and multiply it then divide it by G-10 m/s/s and you get your answer!

yeah, but that gives the answer of 17.6m which is blatantly wrong.


Sinister: I would do it on my computer but then i have to type formulae etc and i tend to scrawl everywhere when i'm trying to work something out.

Endymion
05-18-2005, 04:23 PM
just a second, let me find a pen.

Noodles is gay
05-18-2005, 04:26 PM
YAY!!!!! My hero! :D

Endymion
05-18-2005, 04:28 PM
first, time to get to net = 5.5m / 32m/s = .171875s.
second, drop length: using simple calculus you find that x = a/2*t^2+v0*t+x0, reorganizing and setting v0=0 leaves us with x0-x=-a/2*t^2 = -(-10m/s^2)/2*(.171875s)^2 = .147705m.

you can unblock me on msn now, thank :(.

Noodles is gay
05-18-2005, 04:38 PM
first, time to get to net = 5.5m / 32m/s = .171875s.
second, drop length: using simple calculus you find that x = a/2*t^2+v0*t+x0, reorganizing and setting v0=0 leaves us with x0-x=-a/2*t^2 = -(-10m/s^2)/2*(.171875s)^2 = .147705m.

you can unblock me on msn now, thank :(.

er.......THANK YOU!!!

but why did you divide gravity by two?: -(-10m/s^2)/ :confused:



you're not blocked, are you.....? :o

Endymion
05-18-2005, 04:45 PM
when assuming a constant acceleration system (such as the surface of the earth), we start out with x'' = a. integrate that and you get x' = a*t + v0, integrate again and you get x = a/2*t^2 + v0*t + x0. in this case, a = g = -10m/s^2

Endymion
05-18-2005, 04:46 PM
and i am blocked, meany-head.

Noodles is gay
05-18-2005, 04:51 PM
ok, I think i get that; thank you very much. Damn you're good at physics - I wish you could do my exam for me :(


ah, sorry about that - I blocked practically everyone so that i wouldn't be tempted to talk to them whilst I was supposed to be revising. :o yes...very sorry indeed - I shall unblock you post haste but i cannot talk because I have to go to bed :(

but thank you very much for the physics! :)

JohnnyNemesis
05-18-2005, 04:51 PM
Unblock me while you're at it, physics geek! :P

punkangel
05-18-2005, 05:14 PM
A tennis player is standing 5.5m from the net. She hits the ball horizontally at a speed of 32m/s. How far has the ball dropped when it reaches the net? Take g = 10m/s/s.

Can anybody work that out? And tell me how to do it please? I have been trying for almost an hour now, i've gone through a ridiculous amount of paper and still have nothing! :mad: It's really simple and i must be missing something because otherwise i would have it but no!

so yeah, dammit, where is Endymion when i need him?



sorry, not good at math...to prove it, look at my grade

miracle I'm still passing

Brines
05-18-2005, 05:16 PM
Haha, you lied about that too, you loser.

punkangel
05-18-2005, 05:22 PM
Haha, you lied about that too, you loser.


I have a B in that class..that's like failing to me

Brines
05-18-2005, 05:23 PM
So you're not in calc, I suppose? And what happened to you saying, "I have all A's moron?" Besides, you forgot a comma after A's, you moron.

ShadowPyro
05-18-2005, 05:27 PM
I cant help, i suck at math sorry... I have 59.8% right now... lol.

Endymion
05-18-2005, 05:29 PM
oddly enough, i'm getting all As this semester... i usually have a mix of As and Bs.

Endymion
05-18-2005, 05:30 PM
Unblock me while you're at it, physics geek! :P

you talkin' to me? 'cause i don't have you blocked... or added, for that matter. THIS WILL SOON CHANGE!

Endymion
05-18-2005, 05:31 PM
which do you prefer using, msn or yahoo? i'm down with both, just add me to whichever. or both. win!

JohnnyNemesis
05-18-2005, 05:34 PM
you talkin' to me? 'cause i don't have you blocked... or added, for that matter. THIS WILL SOON CHANGE!

I meant NiG, though it would have made more sense if I was talking to you. Add me on all three, though I'm rarely on Yahoo. Do dat ish, homie!

Noodles is gay
05-18-2005, 05:49 PM
I meant NiG, though it would have made more sense if I was talking to you. Add me on all three, though I'm rarely on Yahoo. Do dat ish, homie!

I'm not a physics geek......

JohnnyNemesis
05-18-2005, 05:50 PM
I know, I was kiddin'