/sci/ - Science & Math

[Anonymous No.2192207]

Hi. physicsfag with not-so-great math skills, here.

I have a mass density function, call it p(r), and I don't know how to integrate to figure out the acceleration due to gravity on some object at position x. I know that the acceleration is proportional to the inverse of the square of the distance to the source.

I want to integrate G*p(r)/(x-r)^2 from r = 0 to r = x, then subtract from that the same integral from r = x to r = infinity to find the acceleration of x.. but I don't feel confident about this.

[Anonymous No.2192260]

CAN YOU HELP FOR THESE PROBLEM I DONT HOW CAN I SOLVE THESE PROBLEM

[Anonymous No.2192261]

[Anonymous No.2192290]

[Anonymous No.2192317]

buump

[Anonymous No.2192319]

you really should do your own homework

[Anonymous No.2192327]

that approach sounds legit to me

[Anonymous No.2192331]

>>2192319
I'm tryying

[Anonymous No.2192335]

>>2192207
The mass differential is 4\pi p(r) r² dr assuming polar coordinates.

[Anonymous No.2192337]

>>2192335
>polar
spherical of course

[Anonymous No.2192342]

>>2192331
youre not trying whatsoever if you dont show your work up until now

[Anonymous No.2192351]

>>2192335
Sorry, I'm not getting this. What is a mass differential?
>>2192342
I showed all my work in the original post, pretty much.
I also worked out the center of mass of my distribution, but it seems pretty useless because I can't figure out what mass to use as the point mass at that center.. because it must be less than the total mass.

[Anonymous No.2192375]

>>2192351
are x and r radii in spherical coordinates or are they vectors ?

[Anonymous No.2192498]

>>2192375
It's a one-dimensional problem, so the answer is yes :P