# DJBruce

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## Posts posted by DJBruce

### Falling Through The Earth

So our instructor posed this question to use at the beginning of the year. What would happen if you where to drill a hole straight through the center of the Earth and jump in (all technicalities aside including air resistance).

Well just thinking about the problem I think that you you would make it to the exact other side of the Earth because gravity would be decelerating you for the same amount of time as it would be accelerating you. But I want to be able to show this mathematically. So I have came up with this. I would appreciate if people would say if this is right and if it is wrong could you point me in the right direction.

V=$\sqrt{2GH}$

You would be accelerating till you reach the center of the Earth so you could use the above equation to figure out how fast you are going when you reach the center of the Earth.

V=$\sqrt{(2)(9.8)(6356750)}$=11162.0921

No I figured once you pass the center of the Earth you could say that you are falling up (or begin shot upwards) and so you could use this equation to figure out how high you will get.

-1/2(G)(X$^{2}$)+(V$_{o}$)(x)+H$_{o}$

-1/2(9.8)(X$^{2}$)+(11162.0921)(X)+0

When you figure out the maximum you find that the maximum height you could reach is 6356669 which I feel is with in the realm of error of say that you would make it to exactly the other side of the Earth.

I do apologize but I was checking my math and noticed a few errors. I have correct my mistakes.

But Kyrisch you are saying that the 81 meter difference is not error but instead will be what causes you to yo yo back and forth until you reach the center of the Earth. My question is why would this happen. Even if gravity changes as you approach the centre of the Earth gravity would be pulling you down (accelerating you) just as long as it is pulling you back to the center (decelerating you). Wouldn't it.

### Help me out here

You have 1 inch cubes you want all there dimensions (x,y,z) of the cube to equal 2. So I put 2 cubes together [][]and that means that my x dimension is 2. Then I add one above it to make y equal two []

[][]

in order to make a square (when you look at it from the top) i need to add another square to the top right [][]

[][]

so now I have a cube that has dimensions of 2,2,1 ans so far I have used 4 boxes so now I need to make my z dimensions equal to so I stack two sets of these 4 cubes on top of each other.

from the top

[][]

[][]

from the side

[][]

[][]

I hope this makes sense if not just use dice or any other small cubes you have.

As for the bullet question both bullets will hit Earth for the most part at the same time because gravity effects each bullet equally.

### All ciphers are crackable? BULLSPIT!!!

Everything is crackable it is just a matter of how much time and effort you are willing to put into cracking it. Im in no way saying that I could crack it but as history shows us everything can and most likely will eventually be cracked.

### Falling Through The Earth

So our instructor posed this question to use at the beginning of the year. What would happen if you where to drill a hole straight through the center of the Earth and jump in (all technicalities aside including air resistance).

Well just thinking about the problem I think that you you would make it to the exact other side of the Earth because gravity would be decelerating you for the same amount of time as it would be accelerating you. But I want to be able to show this mathematically. So I have came up with this. I would appreciate if people would say if this is right and if it is wrong could you point me in the right direction.

V=$\sqrt{2GH}$

You would be accelerating till you reach the center of the Earth so you could use the above equation to figure out how fast you are going when you reach the center of the Earth.

V=$\sqrt{(2)(9.8)(6356750)}$=3529.74

No I figured once you pass the center of the Earth you could say that you are falling up (or begin shot upwards) and so you could use this equation to figure out how high you will get.

-1/2(G)(X$^{2}$)+(V$_{o}$)(x)+H$_{o}$

-1/2(9.8)(X$^{2}$)+(3529.74)(X)+0

When you figure out the maximum you find that the maximum height you could reach is 635666.55 which I feel is with in the realm of error of say that you would make it to exactly the other side of the Earth.

### physics w/ algebra vs physics w/calc

I live in what I would call a average normal American public school. I am a sophomore and have taken the most advanced classes my school offers and I can not even take calculus til my senior year. Here is a brief description of our math system. (We use a course of books designed by the University of Chicago.

Now here's where it gets a little weird

10th grade- We do a lab class where you cover Algebra 2 and the first half of a book called Functions, Statistics and Trigonometry.

11th grade- we finish Functions, Statistics and Trigonometry We then finish a book call PreCalculus desreate mathematics. (this is a mostly self taught lab class)

12th grade-We take AP Statistics and a Calculus course that allows students to take the AP test (sorry I don't know which one).

And nothing beyond Algebra one which can be taken as a three year class if you can not pass the normal class.

Maybe I'm confused or is Americas education system just that bad and slow.

### So, You Think Relativity is Wrong

I have posted my answer to the question. I have no idea if this is even close but heres my best shot at this. Please do not read if you do not want a POSSIBLE spoiler.

The total kentic energy of the system is 15000.

E$_{}K$=1/2MV$^{2}$

So when yellow is my refrence the energy of my system is

1/2(1)(100$^{2}$)+1/2(1)(100$^{2}$)=10000

but this doesnt mean that the yellow ball is not moving so when we use the red ball is the reference it the energy of my system is

1/2(1)(100$^{2}$)=5000

If you add these you would be able to find the Kinetic energy of the system.

As I said I have no idea if this is right but thats my best shot.

### Germans claim to break the speed of light

It found this I know its not a very good source but I think that this is intresting and could be very big.

Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz in Germany, claim to have broken the speed of light. They have conducted an experiment in which microwave photons traveled "instantaneously" between a pair of prisms that had been moved up to 3ft apart, which would be faster than the 186,000 MPH that Albert Einstein once said would take an infinite amount of energy to power.

I also have a question if microwaves are part of the Elecormagnetic spectrum dont they already go at the speed of light?

### Teaching Myself Physics

trying to do the same thing

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