Arch welding voltage (open circuit) ranges between 20V and 100V. AC electric current at 415 V and 50Hz is supplied to an arch welding transformer that steps down the voltage to 35V for welding. Calculate the number of turns in the primary coil when the secondary coil has 40 turns.

• A. 474 turns
• B. 3 turns
• C. 166 turns
• D. 277 turns

Answer: (A)