Gravitational Attraction Question

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
42 replies · 10K views
the { } is square root
 
Physics news on Phys.org
i got to X = D-X{Me} / {Mm}
 
wilson_chem90 said:
i got to X = D-X{Me} / {Mm}
OK, write that as:
X = (D-X) {Me/Mm} (using {} for square root)

Now solve for X. (Get all the X terms on the same side.)
 
so would it just be X+X = D {Me/Mm}
 
wilson_chem90 said:
so would it just be X+X = D {Me/Mm}
No. Realize that:

X = (D-X) {Me/Mm} →

X = D{Me/Mm} - X{Me/Mm}
 
oh okay, yeah i remember that now, is that the final equation though?
 
well i have to isolate the other x right, but the only think i can think of is it would be X^2 = D{Me/Mm} - {Me/Mm}
 
wilson_chem90 said:
well i have to isolate the other x right, but the only think i can think of is it would be X^2 = D{Me/Mm} - {Me/Mm}
No. You must isolate X, but you don't end up with X^2.

How would you solve this one?

x = a -bx (a and b are just constants)

It's the same basic equation.
 
would it be x = a/b?
 
wilson_chem90 said:
would it be x = a/b?
No. Do it step by step:

x = a - bx

group the x terms on the left:
x + bx = a

factor out the x:
x (1 + b) = a

isolate the x by dividing both sides by (1 + b):
x = a/(1 + b)

done!
 
YES! finally, thank you so much. i appreciate your time and patience with me