Question

which symbol and unit of measurement are used for electric current?
○ symbol: a; unit: i
○ symbol: c; unit: a
○ symbol: i; unit: c
○ symbol: i; unit: a

Explanation:

To determine the symbol and unit for electric current, we recall physics concepts: Electric current is represented by the symbol \( I \) (from "intensity of current") and its SI unit is the ampere, abbreviated as \( A \). Let's analyze each option:

• First option: Symbol \( A \) (ampere is a unit, not the symbol for current) and unit \( I \) (incorrect, \( I \) is the symbol, not a unit) → wrong.
• Second option: Symbol \( C \) (coulomb, unit of charge) and unit \( A \) → wrong symbol.
• Third option: Symbol \( I \) (correct symbol) but unit \( C \) (coulomb, unit of charge) → wrong unit.
• Fourth option: Symbol \( I \) (correct) and unit \( A \) (ampere, correct unit for current) → correct.

Answer:

D. symbol: \( I \); unit: \( A \) (assuming the last option is D, as per the order: the four options are likely labeled as A, B, C, D with the last one being symbol: \( I \); unit: \( A \))