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Problem

AttheGates1996

Problem
November 06, 2007, 04:00:42 PM
Your cable has gone out for the last time. You are completely fed up now. In fact, you are so angry that you grab your cable box, rip it from the wall and television set, and hurl it out the window. The only problem with this is that you live on the 7th floor of a condominium plaza in downtown Atlanta, which happens to be 98 feet high. In your fit of rage, the initial velocity of your cable box was 25 ft/sec. How long will it take the cable box to hit the car parked below your window if the car is 4 feet tall?


Re: Problem
November 06, 2007, 05:20:07 PM
just enough time to scream the word fuck
Because I am more intelligent than you are.

Re: Problem
November 06, 2007, 05:33:36 PM
I haven't done this in some time, and I was horrible with mechanic, but here you go.

This is a pretty straightforward problem that can be solved with classical mechanics.

We'll use this equation.

Y=Yi + Vy * T -1/2 * a * T^2

where
Y is the height of the box after T seconds
Yi is the initial height before you throw the box (If you throw the box from 98 feet high, and the car is 4 feet high, it has to travel 94 feet to hit it, so Yi=94 feet )
Vy is the initial vertical speed of the box (0 in that case
T is the time in seconds
a is the acceleration of the box (the acceleration given by the force of gravity : 9.8 m/s^2 or 32 feet/s^2)

When the box will hit the car, Y will be equal to 0.

0=94 feet + 0 feet *T sec - 1/2 * 32 feet * T^2 square sec

You have only one unknown value therefore you can solve it.

-94 =-16T^2
5.975 = T^2

so T is equal to either 2.4 or -2.4 seconds. You can reject the -2.4 second since it's impossible for the box to hit the car before you threw it :).

And if you want to know whose car you will hit, you can use this equation.

X = Vx * T

Where
X is the distance the box will travel in T seconds
Vx is the initial speed of the box (25 feet / seconds)
T is the time (the 2.4 seconds we found in the other equation)

X sec = 25 feet/sec * 2.4 sec
X = 60 feet

So the owner of the car that is 60 horizontal feet away from your room will be the new owner of your broken cable box!

Anyway I didn't factor the air resistance because I don't know it by heart (and I didn't feel like looking for it).

AttheGates1996

Re: Problem
November 06, 2007, 06:21:22 PM
Wow, very impressive. I suck at physics. However, the reason I posted this problem was that of sheer boredom because I know how to solve this from a math modeling standpoint.

Y = a(t^2) + Vi(t) + Yi

Y = -32(t^2) + 25(t) + 98

Now comes the hard partÖha, plug it into your graphing calculator, also plug in Y = 4 for the height of the car and find the intersection and you get 2.15 seconds (the x value of the intersection).

I found it intriguing to have studied physics for a year and then be told how it relates to the quadratic function.  

Re: Problem
November 06, 2007, 06:22:43 PM
This post is an excellent example of why this "Chasm" section never should have been started.

Recognize that when you spam a bunch of inconsequential bullshit, it builds up, like a garbage dump, and drowns everything of value out.

Stop.

Re: Problem
November 06, 2007, 06:44:20 PM
Quote
Wow, very impressive. I suck at physics. However, the reason I posted this problem was that of sheer boredom because I know how to solve this from a math modeling standpoint.

Y = a(t^2) + Vi(t) + Yi

Y = -32(t^2) + 25(t) + 98

Now comes the hard part…ha, plug it into your graphing calculator, also plug in Y = 4 for the height of the car and find the intersection and you get 2.15 seconds (the x value of the intersection).

I found it intriguing to have studied physics for a year and then be told how it relates to the quadratic function. †


This is great and all, but the horizontal speed has no effect whatsoever on the time it takes for the box to hit the car (if I understood the problem properly, the intial vertical speed is 0, while the initial horizontal speed is 25 feet/sec) . In fact, the horizontal speed will stay the same for the complete duration of the throw (there's no force on the box that acts on it horizontally to change it). So if you want to just plug it in your calculator and get the right answer (which is 2.4 sec and not 2.15), you need to use the equation I wrote in my post.

I do agree though that this forum is probably not the best place to post mindless topics when you're bored.

Re: Problem
November 06, 2007, 06:46:51 PM
The answer to the yet unasked question of where to post your ephemeral thoughts is to start a blog with the rest of the losers far, far away from here.

Re: Problem
November 06, 2007, 11:50:29 PM
Quote
Stop.


http://www.anus.com/metal/hall/YaBB.cgi?board=deathmetal;action=display;num=1190685761

This is an experiment and the results are apparently still unseen to most. A basic pattern is obviously forming to those with keen eyes and a decent amount of common sense and life experience: this sub-forum is quickly turning into a pool of useless, meaningless shit not unlike the typical commercials coming out of a television set. Ask yourself: are more meaningful topics appearing here or somewhere more regulated? Point proven: People need to be regulated or they will produce an exponentially large amount of trivial blabber.

Mods: back to work!  ;)

Re: Problem
November 07, 2007, 12:15:33 AM
Quote

http://www.anus.com/metal/hall/YaBB.cgi?board=deathmetal;action=display;num=1190685761

This is an experiment and the results are apparently still unseen to most. A basic pattern is obviously forming to those with keen eyes and a decent amount of common sense and life experience: this sub-forum is quickly turning into a pool of useless, meaningless shit not unlike the typical commercials coming out of a television set. Ask yourself: are more meaningful topics appearing here or somewhere more regulated? Point proven: People need to be regulated or they will produce an exponentially large amount of trivial blabber.

Mods: back to work! †;)


If you recognize the truth in all of the above, then 1) stop posting in and reading this particular sub-forum, and/or 2) post something meaningful to overcome the stupid.

All moderation needn't be applied directly and externally if enough of us agree on what we find meaningful and what we don't.  Judging by the recent rise in distaste for The Chasm we seem to have fair number so let's get busy.

shadowmystic

Re: Problem
November 07, 2007, 04:42:21 AM
I'm surprised people here don't appreciate The Chasm actually, if you were referring to the band, hard to tell because you put a capital for the T, otherwise I would have assumed you were talking about this forum.

Re: Problem
November 07, 2007, 05:23:24 AM
At this point I would like to suggest that anyone who uses the imperial system has AIDS.

Re: Problem
November 07, 2007, 06:03:36 AM
The Chasm is here for a reason.  Waste is posted here so that intelligent conversation can be kept to the real forum.

Seriously, this shit has to go somewhere.

AttheGates1996

Re: Problem
November 07, 2007, 04:43:27 PM
I donít see what the big deal is. Iím not for or against anything you guys are saying simply because I donít even consider it to be worthy of debate. Itís just a forum, and itís just casual talk.

At least these Chasm conversations are intellectual and not people randomly posting how their day went. They are simply more intellectual by nature because we are all the open-minded that listen, appreciate and have the ability to comprehend music in its finest forms.