Electrical Engineering - Capacitors - Discussion

Discussion Forum : Capacitors - General Questions (Q.No. 17)
17.
Two series capacitors (one 2 F, the other of unknown value) are charged from a 24 V source. The 2 F capacitor is charged to 16 V and the other to 8 V. The value of the unknown capacitor is
1 F
2 F
4 F
8 F
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
9 comments Page 1 of 1.

DIBYAJYOTI BEHERA said:   5 years ago
Thanks all for explaining.

Ravi said:   7 years ago
You are correct, Thanks @Ashok.

Kumaraswamy said:   9 years ago
You are Correct @Snigdharani Das.

Snigdharani das said:   10 years ago
Data given as c1 = 2 microfarad, v1 = 16V; v2 = 8V, c2 = ?

In series circuit current is same. In 1st capacitor charge store q1 is c1xv1 = 2x16 = 32 microcoulomb.

So c2 = q/v2 = 32/8 = 4 microfarad.

Answer: 4 microfarad.
(4)

Bharath said:   1 decade ago
C1*V1=C2*V2.

Because C is indirectly proportional to V.

Abc said:   1 decade ago
q=cv.

So c=q/v.

Charging is indirectly proportional to voltage.

Mohamed sherif said:   1 decade ago
I think this is wrong.

v = I/Xc.
Xc = 1/(2pi*f*c).
v = I*(2pi*f*c).
v1 = I*(2pi*f*c1).

As they are in series so the same I & also f of the circuit is the same.

v2 = I*(2pi*f*c2).
v1/v2 = c1/c2.
8/16 = c1/2.
c1 = 1.

Femi said:   1 decade ago
For series; the capacitors diminish,

Let v2 = x
1/2 = 16v
1/x = 8v
4x=16.....
x = 4

Ashok said:   1 decade ago
Current is same in series circuit. Here two capacitors r in series, so charge of each capacitor is also same.

The charge of 1st Cap. is; Q = C1 x V1 = 2 x 10^-6 x 16 = 32 microF.

From this Therefore, second Cap.; C2 = Q/V2 = (32 x 10^-6)/8 = 4 microF.
(1)

Post your comments here:

Your comments will be displayed after verification.