Question

help me please!!,,,to the plate plane air capacitor applied potential difference U = 500V in the area of ​​the plates with a = 200 cm square, the distance between d1 = 1,5 mm.
plates moved apart to a distance d2 = 15mm.
find the energy E1 and E2 of the capacitor before and after razdvizheniya plates, if the source of EMF to razdvizheniem:
1) switched off, and 2) does not turn off. (1) E1 = 14,8 mJ, E2 = 148mkdzh;
2) E1 = 14,8 mJ: E2 = 1,48 mJ

Answer 1

can you explain what is "razdvizheniem"

Answer 2

that is supposed to the word( motion),,,i translated from russian to english

Answer 3

you have given answer also ... you need procedure ... right ?

Answer 4

yes,plesae

Answer 5

answers are in milli J or in micro J .... coz ... I am getting answers in micro J

Answer 6

\[\int\limits_{o}^{a}d _{x}\]

Answer 7

what is important is the procedure os can you show me ?

Answer 8

I am typing ... I will send in few minutes ..

Answer 9

o right

Answer 10

Formulas required
\[C=\epsilon_0\frac{A}{d}\]
\[Q=CV\]
\[E=\frac{1}{2}CV^2\]
given
\[A=200 cm^2 = 0.02 m^2\]
\[d_1=1.5 mm= 1.5e-3 m\]
\[d_2=15 mm= 15e-3 m\]

Calculating Capacitance:

\[C_1=1.1805e-010\]
\[C_2=1.1805e-011\]

Case 1: when external supply voltage is cut off
before movement voltage is give as
\[V_1=500\]
Finding charge
\[Q=C_1V_1=5.9027e-008\]
after movement charge is constant. So voltage changes to
\[V_2=\frac{Q}{C_2}=5000\]

Finding energy
\[E_1=\frac{1}{2}C_1V_1^2=1.4757e-005 \approx 14.8\mu J\]
\[E_2=\frac{1}{2}C_1V_1^2=1.4757e-004 \approx 148 \mu J\]


Case 2: when external supply voltage is maintained at 500V
Voltage is constant V_1=V_2=V=500v
Finding energy:
\[E_1=\frac{1}{2}C_1V^2=1.4757e-005 \approx 14.8\mu J\]
\[E_2=\frac{1}{2}C_1V^2=1.4757e-006 \approx 1.48\mu J\]

Answer 11

Gina .... I did a mistake .... in the formula of E2 .... the capacitance is not C1 ... it is C2

Answer 12

wow!! thank you very much))

Answer 13

welcome

Answer 14

ok i will check on it

Answer 15

mr.sgadi do have the notes on this topic?

Answer 16

I don't have any special notes regarding this topic. I used Wikipedea.
http://en.wikipedia.org/wiki/Capacitance

Answer 17

thanx again)

Answer 18

:-) welcome

Answer 19

what this about this question of maths,,,,∫oadx

Answer 20

I didn't understand. Can you elaborate?

Answer 21

\[\int\limits_{0}^{a?}d _{x}\]

Answer 22

can help mathamatics?

Answer 23

yes... to an extent. place in new thread so that everyone will be able to help you.

Answer 24

can help mathamatics?

Answer 25

yes. please give the question

Answer 26

\[d _{x}\div \sqrt{x ^{2}+x+1}\]

Answer 27

\[\int{\frac{1}{\sqrt{x^2+x+1}}dx}=\ln{(x+\sqrt{x^2+x+1}+0.5)}\]

Answer 28

yes that is the question

Answer 29

is that the solution?

Answer 30

yes ... I have given the solution also