Question

A circuit is built based on this circuit diagram. What is the equivalent resistance of the circuit?

A. 0.61
B. 1.6
C. 7.5
D. 18

Answer 1

The three resistors are connected to the same points of the circuit, so they are in parallel configuration. The equivalent resistance of 3 resistors in parallel is given by:

`(1)/(R_(eq))= (1)/(R_1)+ (1)/(R_2)+ (1)/(R_3)`
If we plug the values of the resistances into the formula, we find

`(1)/(R_(eq))= (1)/(3.0 \Omega)+ (1)/(6.0 \Omega)+ (1)/(9.0 \Omega)= (6+3+2)/(18.0 \Omega) = (11)/(18.0 \Omega)`
From which we find the equivalent resistance:

`R_(eq) = (18.0)/(11) \Omega =1.6 \Omega`

So, the correct answer is B.