How is 12mA expressed in amperes?

To convert 12 milliamperes (mA) into amperes (A), it's essential to understand the relationship between the two units. The prefix "milli" signifies one thousandth (1/1000) of the base unit, which means that 1 mA is equal to 0.001 A. Therefore, to convert milliamperes to amperes, you divide the number of milliamperes by 1000.

In this case, when you convert 12 mA to amperes, you perform the following calculation:

12 mA ÷ 1000 = 0.012 A.

This means that 12 mA is equivalent to 0.012 amperes.

Thus, the correct representation of 12 mA in amperes would be 0.012 A, which does not align with the given answer of 1.2A. In this situation, the selections of 1.2A, 12A, and 120A are all incorrect conversions based on the fundamental definitions of the measurement units.

Understanding this conversion is crucial in electronic access control where accurate readings of electrical parameters are needed for system design and troubleshooting.