Kansas Mechanical Journeyman Practice Test

To determine the maximum number of amps a 40 VA, 120 V transformer with a 24 V secondary can carry, we first need to understand the relationship between volts, amps, and volt-amperes (VA). The apparent power in volt-amperes (VA) is given by the formula:

\[ \text{Power (P in VA)} = \text{Voltage (V)} \times \text{Current (I in Amps)} \]

We know the transformer is rated for 40 VA, meaning it can deliver up to 40 volts times a certain current. Given that the secondary voltage is 24 V, we can rearrange the formula to solve for the current:

\[ I = \frac{P}{V} \]

Substituting in the known values:

\[ I = \frac{40 \, \text{VA}}{24 \, \text{V}} \]

Calculating this gives:

\[ I = \frac{40}{24} \]

\[ I = 1.6667 \, \text{A} \]

When rounded, this approximates to 1.7 A. Thus, the correct answer is indeed 1.7 A, as this is the