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rearranging formulea

I need some help with rearranging some equations I got for my homework on enrolment day to college.

1.Make “x” the subject of E = ½ k x2
2.Make “G” the subject of V = -GM/r
3.Make “k” the subject of T = 2*pie√(m/k)
4.Make g the subject of T = 2√(l / g)
5. Make “C” the subject of f =1/2*pie√ (LC)
Thanks in advance ( some working would be appreciated)
:wink:
(edited 7 years ago)
Original post by kszyni1
I need some help with rearranging some equations I got for my homework on enrolment day to college.

1.Make “x” the subject of E = ½ k x2
2.Make “G” the subject of V = -GM/r
3.Make “k” the subject of T = 2√(m/k)
4.Make g the subject of T = 2√(l / g)
5. Make “C” the subject of f =___1____
2√ (LC)
Thanks in advance ( some working would be appreciated)
:wink:


you just undo one thing at a time e.g.

1.
E = 1/2 k x2 (assume that's meant to mean squared)
x 2
2E = k x2
divide by k
(2E)/k = x2
square root
2E/k = x

so for number 2 you need to get rid of /r first (so multiple by r) then get rid of xM then get rid of your negative
Reply 2
ok thanks a lot but I'm not too sure how I am supposed how to do the last one but I've got all the other one done but I'm stuck on the last one don't know to work it out. help with the last one please? :tongue:
Original post by doodle_333
you just undo one thing at a time e.g.

1.
E = 1/2 k x2 (assume that's meant to mean squared)
x 2
2E = k x2
divide by k
(2E)/k = x2
square root
2E/k = x

so for number 2 you need to get rid of /r first (so multiple by r) then get rid of xM then get rid of your negative
Original post by kszyni1
I need some help with rearranging some equations I got for my homework on enrolment day to college.

1.Make “x” the subject of E = ½ k x2
2.Make “G” the subject of V = -GM/r
3.Make “k” the subject of T = 2√(m/k)
4.Make g the subject of T = 2√(l / g)
5. Make “C” the subject of f =___1____
2√ (LC)
Thanks in advance ( some working would be appreciated)
:wink:


I'm not sure of how you've written the last one? waht are the underscores and where is the 1root(LC) meant to be? is it meant to be 1/(2root(LC))? if so

f = 1/(2root(LC))
x (2root(LC))
f(2rootLC) = 1
divide by F
2root(LC) = 1/f
divide by 2
root(LC) = 1/2f
square
LC = (1/2f)^2
divide by L
C = ((1/2f)^2)/L

hope that makes sense as I haven't copied the proper symbols in
generally the approach with the more complicated ones is the same, even if you can't see the whole method straight away think 'what can I do?' so in this case the most logical think was to get rid of what was on the bottom of the fraction on the right side and once that happened it was fairly straightforward
Reply 4
Oops sorry my bad it didn't copy correctly sorry my bad.
f = 1 / 2*pie symbol*√ (LC)
sorry again it didn't copy the pie symbol for some reason :/


Original post by doodle_333
I'm not sure of how you've written the last one? waht are the underscores and where is the 1root(LC) meant to be? is it meant to be 1/(2root(LC))? if so

f = 1/(2root(LC))
x (2root(LC))
f(2rootLC) = 1
divide by F
2root(LC) = 1/f
divide by 2
root(LC) = 1/2f
square
LC = (1/2f)^2
divide by L
C = ((1/2f)^2)/L

hope that makes sense as I haven't copied the proper symbols in
generally the approach with the more complicated ones is the same, even if you can't see the whole method straight away think 'what can I do?' so in this case the most logical think was to get rid of what was on the bottom of the fraction on the right side and once that happened it was fairly straightforward
Original post by kszyni1
Oops sorry my bad it didn't copy correctly sorry my bad.
f = 1 / 2*pie symbol*√ (LC)
sorry again it didn't copy the pie symbol for some reason :/


that doesn't change much, you're not solving the equation you're just making a certain thing the subject

so if it's 2pie rather than just 2... on the step where you divide by 2, divide by 2pie and take them out together so it would be 2*pie*f
Reply 6
Ok thank you very much :wink: thanks for the great help
Original post by doodle_333
that doesn't change much, you're not solving the equation you're just making a certain thing the subject

so if it's 2pie rather than just 2... on the step where you divide by 2, divide by 2pie and take them out together so it would be 2*pie*f

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