How many letters does the top answer for “a material's opposition to the flow of electric current; measured in ohms” have?

The most common answer is impedance (9 letters).

Crossword clue: a material's opposition to the flow of electric current; measured in ohms

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

impedance 9 letters wn-def

a material's opposition to the flow of electric current; measured in ohms

resistivity 11 letters wn-def

a material's opposition to the flow of electric current; measured in ohms