Question

30.
Find the value ofr if I = 1 A and potential difference across PQ is 1 V
3222
(A) 50
(B) 100
(C) 20
(D) 25​

Answer 1

Answer:

What is 3222 in the question?

Explanation:

I consider that I is 1 A and V(PQ)=1 V.

3 and 2 ohm are in parallel, so R1=6/5 ohm

r and 1 ohm are in series, so R2=(r+1) ohm

This R2 will be in series with 4 ohm for potential across PQ.

Net Equivalent resistance across PQ=1 ohm

Solving that,

r=1 ohm.

Query: Is 1 A across the PQ or from the battery?

In the latter case, r is 20 ohms.