Question

In an electric generator, the voltage induced across the terminals of the copper coil when it rotates in the magnetic field is ______.

• A. An alternating voltage
• B. Direct voltage
• C. Step-up voltage
• D. Step down voltage

Answer 1

The correct option is A

An alternating voltage

The explanation for the correct option: (A)

1. An alternating voltage is any voltage that varies in both magnitude and polarity with respect to time.
2. An electric generator is an application of electromagnetic induction.
3. In electromagnetic induction alternating current is produced hence alternating voltage.
4. Thus, in an electric generator magnetic field is an alternating voltage.

The explanation for the incorrect option: (B),(C),(D)

1. option: (B): A direct voltage is a voltage that forces electrons to move through a circuit in the same direction continuously, thereby producing a direct current.
2. Direct voltage is used in DC motor as it needs current in the same direction continuously.
3. option: (C): A step-up voltage in a circuit increases the voltage and a Stepdown voltage in a circuit decreases the voltage.
4. option: (D): Step-up voltage and step-down voltage are used in transformers.

Hence, In an electric generator, the voltage induced across the terminals of the copper coil when it rotates in the magnetic field is alternating voltage.

Option (A) is correct.