- #1

eutopia

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this problem probably took me a whole hour but it seems like i don't know what I'm doing wrong...

diagram: http://loncapa.elps.k12.mi.us/cgi-bin/plot.gif?file=MaMargaret_elps_1115513252_23407965_plot.data&output=png

Capacitor MR=78.9 nF

Capacitor PL=38.3 nF

Capacitor TN=35.3 nF

Capacitor US=38.5 nF

Calculate the charge on plate S, if the charge on plate L is 6.51e-8 C. (right) Answer: 9.72e-8 C

Calculate the charge on plate R, if the charge on plate N is 7.29e-8 C.

(wrong) answer: 5.324771655e-8 C:

For the first part, I did

[tex] {Q} = {V}{C} [/tex]

[tex] {Q} = 6.51e-8[/tex]

[tex] {C} = [ 78.9/(78.9+38.3) ] times 38.3e-9 = 2.578e-8[/tex]

[tex] {V} = Q/C = 2.5348[/tex]

the second charge would then be: [tex] {Q} = (38.5e-9)(2.5348) [/tex]

For the second part, I used the same process and got 5.324771655e-8 Columbs but it seems to be wrong, at least the computer says it's wrong, and I can't figure out what's wrong:

[tex] {Q} = 7.29e-8 [/tex]

[tex] {C} = 35.3e-9 [/tex]

[tex] {V} = (7.29e-8)/(35.5e-9) = 2.0651558 [/tex]

-------------------

[tex] {V} = [ 38.3/(78.9+38.3) ] (2.0651558) = .6748760019 [/tex]

[tex] {C} = 78.9e-9 [/tex]

[tex] {Q} = 5.32477e-8 [/tex]

diagram: http://loncapa.elps.k12.mi.us/cgi-bin/plot.gif?file=MaMargaret_elps_1115513252_23407965_plot.data&output=png

Capacitor MR=78.9 nF

Capacitor PL=38.3 nF

Capacitor TN=35.3 nF

Capacitor US=38.5 nF

Calculate the charge on plate S, if the charge on plate L is 6.51e-8 C. (right) Answer: 9.72e-8 C

Calculate the charge on plate R, if the charge on plate N is 7.29e-8 C.

(wrong) answer: 5.324771655e-8 C:

For the first part, I did

[tex] {Q} = {V}{C} [/tex]

[tex] {Q} = 6.51e-8[/tex]

[tex] {C} = [ 78.9/(78.9+38.3) ] times 38.3e-9 = 2.578e-8[/tex]

[tex] {V} = Q/C = 2.5348[/tex]

the second charge would then be: [tex] {Q} = (38.5e-9)(2.5348) [/tex]

For the second part, I used the same process and got 5.324771655e-8 Columbs but it seems to be wrong, at least the computer says it's wrong, and I can't figure out what's wrong:

[tex] {Q} = 7.29e-8 [/tex]

[tex] {C} = 35.3e-9 [/tex]

[tex] {V} = (7.29e-8)/(35.5e-9) = 2.0651558 [/tex]

-------------------

[tex] {V} = [ 38.3/(78.9+38.3) ] (2.0651558) = .6748760019 [/tex]

[tex] {C} = 78.9e-9 [/tex]

[tex] {Q} = 5.32477e-8 [/tex]

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