Question

which two wire properties would provide the greatest resistance to the flow of a current?
o short, thin
o long, thin
o hot, thick
o cool, thick

Explanation:

Step1: Recall resistance formula

The resistance formula is $R =
ho\frac{l}{A}$, where $
ho$ is resistivity (a property of the material), $l$ is length, and $A$ is cross - sectional area. Resistance is directly proportional to length and inversely proportional to cross - sectional area. Also, for most materials, resistance increases with temperature.

Step2: Analyze each option

• Short wires have less length ($l$) so lower resistance.
• Long wires have more length ($l$) so higher resistance.
• Thin wires have smaller cross - sectional area ($A$) so higher resistance.
• Thick wires have larger cross - sectional area ($A$) so lower resistance.
• Hot wires have higher resistivity ($

ho$) for most materials, increasing resistance, while cool wires have lower resistivity.

Answer:

B. long, thin