Question

Dynamo converts:
(a). Electric energy into magnetic energy
(b). Magnetic energy into potential energy
(c). Mechanical energy into electrical energy
(d). No energy

Answer 1

- Hint: A dynamo is also known as a generator is an electric device that produces alternating current.

Complete step-by-step solution -

The working of a dynamo is based on the principle of magnetic induction. A rectangular coil made up of a large number of turns of insulated copper wires is rotated between two pole pieces of opposite polarity of a strong electromagnet. As the coil is rotated in the magnetic field the angle \[\theta \] between the magnetic field and normal to the coil changes continuously ,therefore the magnetic flux associated with the coil also changes and hence induced emf is developed according to Lenz’s law.
Current is induced in the coil and its direction can be determined by using Flemming’s right hand rule. The induced current changes its direction after every half rotation of the coil. This is how Magnetic energy is converted into alternating induced current.
The correct answer is C. Mechanical energy into electrical energy.

Additional Information:

The magnitude of induced emf \[e\]in the coil is given by:
\[e=NAB\omega \sin \left( \omega t \right)\]
N= number of turns in the coil
A= area enclosed in the coil
The current supplied by the Dynamo is given by:
\[i={{i}_{0}}\sin \omega t=\dfrac{e}{R}\]

Note: It should be noted that nothing is actually generated by this device, the energy is basically converted from one form to another. The generator or dynamo is one of the most used applications of electromagnetic induction and it was designed by Nikola Tesla.