Equivalent capacitance:pentagon shape

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gracy
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Homework Statement


Five capacitors ,each of capacitance value C are connected as shown in the figure.The ratio of capacitance between P and R,and the capacitance between P and Q is
Circuit diagram of five capacitors, each labelled C, connected in a closed pentagon loop with corners labelled P, Q, R, S and T.


Homework Equations


For Equivalent Capacitance in series

##\frac{1}{C}##=##\frac{1}{C_1}##+##\frac{1}{C_2}##

The Attempt at a Solution


But I don't know from which direction should I consider capacitors whether clockwise or anticloclwise?Because I will encounter different number of capacitors in each of these direction.
 
gracy said:

Homework Statement


Five capacitors ,each of capacitance value C are connected as shown in the figure.The ratio of capacitance between P and R,and the capacitance between P and Q is
View attachment 92640

Homework Equations


For Equivalent Capacitance in series

##\frac{1}{C}##=##\frac{1}{C_1}##+##\frac{1}{C_2}##

The Attempt at a Solution


But I don't know from which direction should I consider capacitors whether clockwise or anticloclwise?Because I will encounter different number of capacitors in each of these direction.
Does it matter? is ##\frac{1}{C_1}+\frac{1}{C_2}## not the same as ##\frac{1}{C_2}+\frac{1}{C_1}##?What capacitors are connected in series and in parallel with respect to the terminals P and R, and in case when the terminals are P and Q?
Determine the equivalent capacitance between P and R. Then determine the equivalent capacitance between P and Q. What are they?
 
It seems to me that you are very interested in capacitors and resistors. I recommend that you buy multitester with capacitance measuring capability. Get few resistors and capacitors of different values and make a circuit of any configuration you like.
 
I will try to solve this with the help of answers I have received in my previous thread.
ehild said:
Determine the equivalent capacitance between P and R
Circuit diagram with points P, Q, R, S and T, with capacitors labelled C and C/4 in a pentagon arrangement, beside an equivalent diagram with C/2 and C/3 in parallel between P and R.


Now the two capacitors are in parallel
equivalent capacitance between P and R=C/2+C/3
=##\frac{5C}{6}##
ehild said:
determine the equivalent capacitance between P and Q.
Left: a circuit of capacitors labelled C and R between terminals P, Q, T and S, with a resistor R in the lower branch. Right: the simplified equivalent, a capacitor C between P and Q and a capacitor C/4 between T and S, joined by an arrow.

Now the two capacitors are in parallel
equivalent capacitance between P and Q is =C+C/4
=##\frac{5C}{4}##
The ratio between the two are
##\frac{5C}{6}##÷##\frac{5C}{4}##

=##\frac{2}{3}##

Am I right?
 
gracy said:
I will try to solve this with the help of answers I have received in my previous thread.

View attachment 92647

Now the two capacitors are in parallel
equivalent capacitance between P and R=C/2+C/3
=##\frac{5C}{6}##

View attachment 92648
Now the two capacitors are in parallel
equivalent capacitance between P and Q is =C+C/4
=##\frac{5C}{4}##
The ratio between the two are
##\frac{5C}{6}##÷##\frac{5C}{4}##

=##\frac{2}{3}##

Am I right?

Looks good to me.
 
Splendid!
You did it right, the answers you got in one thread can be applied in an other thread. Do not forget them!
 
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ehild said:
Splendid!
Thank you so much for this .:smile:
 
gracy said:
I will try to solve this with the help of answers I have received in my previous thread.

View attachment 92647

Now the two capacitors are in parallel
equivalent capacitance between P and R=C/2+C/3
=##\frac{5C}{6}##

View attachment 92648
Now the two capacitors are in parallel
equivalent capacitance between P and Q is =C+C/4
=##\frac{5C}{4}##
The ratio between the two are
##\frac{5C}{6}##÷##\frac{5C}{4}##

=##\frac{2}{3}##

Am I right?
Why did you not do this in OP ?

Then, if you were not sure about which order to use, you could have tried any order you were not sure about and compared answers.

That's generally how we know whether or not such things are important.