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The Super Juicy CURRENT YEAR 11 (2012-13) THREAD Mark V

This is a nice problem, and it's differential; [-GM_em/x^2]-[-GM_mm/(r-x)^2]

However, when you equate this to zero you get an issue! You can never have a value of x for which you divide the constants by to get zero! 1/x can never equal zero!

So your graph shoots off to infinite! The solution looks something like this.. (assuming an 80kg astronaut)

However, that would give a solution of around 6'800km. I'm not convinced your original equation was correct though.
The gravitational pull of something is equal to [GM_object]/r^2, so the point where the 2 attractions balance

[G*M_e]/r^2=[G*M_m]/R^2

Given G and the Masses are constant you could solve for R like that.

This may all be rubbish, but just my ideas. Sorry if this wastes your time!

What the **** is this?

Reply 1221

Vionar

13

Original post by Bluffroom

have you even tried it?

Well... no... not really... but the thought of cheese disgusts me, I don't think I've ever eaten cheese out of choice, the first time I could speak out against it, I stopped eating it.

Reply 1222

L'Evil Fish

18

Original post by Bude8

You obviously, L'Evil Fish knows that he shouldn't disrespect the boss.

How do I go about disrespecting myself anyway? :redface:

Reply 1223

zed963

16

Original post by PriyaPaul

Woow looks complicated !! Is this even GCSE ? :tongue:

Looks like A-level stuff to me.

Reply 1224

Enigma Machine

20

Original post by MrGoogle

x

No need to be so polite to the boss :wink:

Answer:

Cancel G and m

Original post by EduWiz

Whos the boss

I'm the boss

Reply 1225

zed963

16

Original post by L'Evil Fish

How do I go about disrespecting myself anyway? :redface:

Good one.

Reply 1226

EduWiz

4

Original post by zed963

Me. Zed has risen to take the throne.

ahahahaahaahahahaahhahahahahah

Original post by zed963

What the **** is this?

i was just thinking the same thing :biggrin:

Reply 1227

MrGoogle

Secondly Bude, solving for where the pulls are equal assumes there is one point. In reality, there's millions of points! So it can't really be solved.. You can't solve the equation I wrote, nor any equation to this end.. You can imagine all the points where the forces are equal, at different distances from the 2 bodies.

Does Bude do IB?

Original post by zed963

Me. Zed has risen to take the throne.

You Zed or this Zed?

Spoiler

Reply 1230

L'Evil Fish

18

Original post by zed963

Good one.

Reply 1231

username1135580

10

Original post by MrGoogle

This is a nice problem, and it's differential; [-GM_em/x^2]-[-GM_mm/(r-x)^2]

However, when you equate this to zero you get an issue! You can never have a value of x for which you divide the constants by to get zero! 1/x can never equal zero!

So your graph shoots off to infinite! The solution looks something like this.. (assuming an 80kg astronaut)

However, that would give a solution of around 6'800km. I'm not convinced your original equation was correct though.
The gravitational pull of something is equal to [GM_object]/r^2, so the point where the 2 attractions balance

[G*M_e]/r^2=[G*M_m]/R^2

Given G and the Masses are constant you could solve for R like that.

This may all be rubbish, but just my ideas. Sorry if this wastes your time!

This doesn't looks complicated, my mind is still trying to get round it

Reply 1232

Enigma Machine

20

Original post by zed963

Does Bude do IB?

This September.

Reply 1233

Bluffroom

11

Original post by Vionar

Well... no... not really... but the thought of cheese disgusts me, I don't think I've ever eaten cheese out of choice, the first time I could speak out against it, I stopped eating it.