Question

What is the total resistance, in units of Ohms, for the circuit shown in the diagram below when measured from the terminals on the left where R1 = 25 Ohms, R2 = 26 Ohms and R3 = 20 Ohms?

(Answer needs to be within one decimal place, in units of Ohms.)

Answer 1

Answer;

≈ 16.2 Ohms

Explanation;

R₂ and R₃ are in series; therefore to get total Resistance, we will use;

= R₂ + R₃

= 26 +20

= 46 Ohms

Then the two resistors (R₂ and R₃) combined and R₁ are in parallel to each other;

Therefore, using the formula for parallel resistors; 1/R₁ + 1/R(₂,₃)

1/Rt =1/25 +1/46

 1/Rt   =(25+46)/(25 ×46)

Rt = (25 ×46)/(25+46

   = 16.197

   ≈ 16.2 Ohms