Question

the green wire has a length of 50 cm
the brown wire has a length of 40 cm
the blue wire has a length of 30 cm
shorter wires have a lower resistance
longer wires have a higher resistance
which of these wires has the lowest resistance?

Explanation:

Step1: Recall the relationship between wire length and resistance

The resistance formula is \(R =
ho\frac{l}{A}\) (where \(R\) is resistance, \(
ho\) is resistivity, \(l\) is length, and \(A\) is cross - sectional area). Assuming same material (\(
ho\)) and cross - sectional area (\(A\)), resistance \(R\) is directly proportional to length \(l\).

Step2: Compare the lengths of the wires

The green wire has a length \(l_{green}=50\space cm\), the brown wire has \(l_{brown} = 40\space cm\), and the blue wire has \(l_{blue}=30\space cm\). Since \(l_{blue}

Answer:

Blue