Question

The equivalent resistance between the points P and Q is​

Answer 1

Answer:

⟹ RPQ=1Ω

Explanation:

Effective resistance of 2Ω and 2Ω in parallel R

AB

=

2+2

2×2

=1Ω

∴ Equivalent resistance between P and Q, R

PQ

=2∥(1+R

AB

)=2∥2

⟹ R

PQ

=1Ω

Answer 2

Answer:

Complete step by step answer:

Let us consider a point, say R at the junction. If we say that the current starts to flow from end P to other branches of the resistors. We can see the flow of the current in the figure given below,

The point R acts as the junction point. So, applying Kirchhoff’s Current Law (KCL) in the circuit, we get,

I+I2=I2+I1

Further solving the above expression, we will get,

I=I1

From this, we can say that the current will flow the same from point P to R, and then R to Q. The current will not flow through the upper part of the circuit. The remaining circuit we will obtain is,

Here, resistors R1 and R2 are in series combination to each other.

So the equivalent resistor of these both can be calculated as,

R=R1+R2

⟹R=2Ω+2Ω

⟹R=4Ω

This obtained equivalent resistance is in parallel combination with the resistor R3. Therefore, the equivalent resistance of the circuit is given as,

1Req=1R+1R3

⟹1Req=12Ω+14Ω

⟹1Req=12Ω+14Ω

⟹Req=43Ω

Therefore, the equivalent between the point P and Q is 43Ω.