Question 389Electricity & Electronics - QMED

The correct answer is A) 0 volts. The question states that the illustrated device in figure "B" has a step-up ratio of 10 to 1. This means that for every 10 volts applied to the primary winding, the secondary winding will produce 1 volt. Since the primary is connected to 110 volts DC, the secondary voltage would be 110 / 10 = 11 volts DC. However, the question asks what the voltage would be "shortly after the primary of the device is connected to 110 volts DC". At the instant of connection, the secondary winding would have 0 volts, as the magnetic field in the transformer is just beginning to build up. Therefore, the correct answer is A) 0 volts.