Question

The device used to produce electric current is known as
1. motor
2. generator
3. ammeter
4. galvanometer

Answer 1

Correct Answer - Option 2 : generator

CONCEPT:

• AC Generators: A machine that converts mechanical energy into electrical energy is AC generators.
  • This electrical energy is in the form of an alternating current of the sinusoidal output waveform.
  • This mechanical energy is generally supplied by gas turbines, steam turbines, and combustion engines. 
• AC generators work on the principle of Faraday’s law which explains electromagnetic induction.
  • This can either be achieved by rotating the magnetic field that contains the stationary conductor or by rotating a conducting coil in a static magnetic field.
  • So it is preferred to keep the coil stationary because it is easier to draw induced alternating current from a stationary armature coil than a rotating coil.

EXPLANATION:

• The device in which electrical energy is converted into mechanical energy is called an electric motor.
• AC generator works on the principle of Faraday's Law.
  • AC generators convert mechanical energy into electrical energy.
  • The generated energy is in the form of a sinusoidal waveform (alternating current). Therefore option 2 is correct.
• An ammeter is an instrument that is used to measure the current flowing through the circuit.
  • It has low resistance, ideally zero.
  • By connecting ammeter in series, it allows all of the circuit current to pass through it and hence measure it.
• Galvanometer: An electro-mechanical instrument used for indicating and detecting electric current.
  • A galvanometer works as an actuator.
  • It produces a rotary deflection, in response to electric current flowing through the coil in a constant magnetic field.