Short Answer 
The equivalent resistance of R3, R4, and R5 in parallel is calculated to be 1.43 ohm. This is then combined with R6 (7.1 ohm) in series, resulting in 8.53 ohm. Finally, the overall equivalent resistance of R1 (1.9 ohm), R2 (2.5 ohm), and the previous result in parallel gives a final equivalent resistance of 0.95 ohm.
Step 1: Calculate the Equivalent Resistance of R3, R4, and R5
To find the equivalent resistance of resistors R3, R4, and R5, which are connected in parallel, use the formula:
- 1 / R = (1 / R3) + (1 / R4) + (1 / R5)
- Substituting the values: R3 = 4.4 ohm, R4 = 3.5 ohm, and R5 = 5.5 ohm gives:
- 1 / R = (1 / 4.4) + (1 / 3.5) + (1 / 5.5) = 0.69
The equivalent resistance R from this calculation is 1.43 ohm.
Step 2: Combine R6 with the Previous Result
The next step involves combining the equivalent resistance calculated in Step 1 with resistor R6, which is in series. The formula used is:
- r = R + R6
- Where R = 1.43 ohm and R6 = 7.1 ohm, leading to:
- r = 1.43 + 7.1 = 8.53 ohm.
Step 3: Calculate the Final Equivalent Resistance with R1 and R2
Finally, R1, R2, and the combined resistance from Step 2 are in parallel. Use the parallel resistance formula again:
- 1 / r = (1 / R1) + (1 / R2) + (1 / 8.53)
- Substituting R1 = 1.9 ohm, R2 = 2.5 ohm results in:
- 1 / r = (1 / 1.9) + (1 / 2.5) + (1 / 8.53) = 1.04 ohm.
The final equivalent resistance R eq is then calculated as R eq = 1 / 1.04 = 0.95 ohm.