Question

What is the current in the circuit shown below?
a) 1.5 A
b) 0.5 A
c) 2.5A
d) none of these​

Answer 1

Answer:

a) 1.5 A

Step-by-step explanation:

Because

In the figure given

let voltages at A,B,C,D be VA,VB,VC,VD.

Let VA>VB.

given VA−VB=16V

let current from A to B be ′i′ (through r1,r4,r5)

let current from C to D through r2 be i1, then current from r3 will be i−i1 from C to D.

On applying 'Kirchhoff's voltage law' in the closed loop with 9V source :-

      9−2(i−i1)+1i1=0

                        ⇒2i - 9/3 ....(1)

On applying 'Kirchhoff's voltage law' from A to B:-

                      VA−4i−9−1i1+3−1i−3i−VB=0

                      ⇒16−8i−6−i1=0 (∵VA−VB=16)

                      ⇒30−26i+9=0(∵ from equation (1))

                     ⇒i=1.5A

                      ⇒i1

Answer 2

Answer:

What is the current in the circuit shown below?

a) 1.5 A

b) 0.5 A

c) 2.5A

d) none of these

Step-by-step explanation:

a) 1.5 A

another example

In steady state, no current flow in the capacitor branch. Thus the current will flow through resistors 2.8, 3 and 2 .

So , total resistance of the circuit is Req=2.8+2∣∣3=2.8+2+32×3=2.8+1.2=4Ω

Thus, current , I=ReqV=6/4=1.5A

As resistor 2 and 3 are in parallel so current I will distribute in their indirect ratio.

Thus, current through resistor 2Ω is i2=2+33I=(3/5)(1.5)=0.9A

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