NEIEP Mechanics Practice Exam

Disable ads (and more) with a membership for a one time $2.99 payment

Prepare for the NEIEP Mechanics Exam with multiple choice questions, hints, and detailed explanations. Ace your test and advance your career!

Practice this question and more.

Which factor is essential for calculating transformer efficiency?

Input current only
Output voltage only
Input and Output values
Turn ratio only

The correct answer is: Input and Output values

To determine the efficiency of a transformer, it is essential to consider both the input and output values. Efficiency is calculated by comparing the output power to the input power, typically expressed as a percentage. Thus, knowing both the input power (which includes the input voltage and current) and the output power (which includes the output voltage and current) is critical to performing this calculation accurately. The input power is determined by the product of the input voltage and input current in the primary winding, while the output power is calculated similarly using the output voltage and current from the secondary winding. The efficiency formula is given by the output power divided by the input power, multiplied by 100 to express it as a percentage. Therefore, both input and output measurements are necessary for this calculation. This understanding allows for a complete assessment of how effectively the transformer operates, highlighting its performance in transferring electrical energy from one circuit to another.