Similarities and differences between AC and DC current:
Alternating Current Direct Current
AC can be safely transferred across a DC cannot travel far because it dissipates
distance whilst carrying electrical current electrical power overtime
The flow of electricity rotates DC flows in a single direction
The frequency is usually around 50 Hz Cannot have 0 frequency
The direction the current flows at may Steadily flows in a single direction
change from time to time
Electrons go back and forth Electrons only move forward
Alternating Current, AC:
Alternating current refers to the continuous modification of charge flow. indicating that
along with the current's direction, the voltage level also changed. In our daily life, AC is used
to transmit power to structures like homes and offices. An electrical generator specifically
constructed to produce alternating current is used to create AC. A wire loop is spun inside a
magnetic field in an alternator, which produces a current along the wire. The wire can be
spun by several things, such as a steam turbine, a wind turbine, or moving water. The
voltage and current on the spinning wire alternate when it occasionally enters a new
magnetic polarity.
Direct Current, DC:
DC offers a constant voltage or current in contrast to AC. There are numerous ways to
produce DC. For instance, direct current can be generated in one way by connecting a
commutator to an AC generator. Utilising a rectifier, which transforms alternating current
into direct current, is another method. To create DC, batteries can also initiate a chemical
reaction.
Fleming’s Left-Hand rule, FLH and Right-Hand rule, FRH:
The key to a magnetic field perpendicular to the wire is an electric current flowing across it.
The wire is moved by this interaction's force. The anchor moves and the motor is operating
because numerous wires are fixed to a rotor (the rotating portion of the motor).
The second finger shows us the current lines, which are coupled to the magnetic field lines
that run from north to south on the fingers.
The thumb indicates the direction of the current-carrying conductor's effect force from the
motor. The Fleming Left Hand Rule (FLHR) is used to determine the direction of force/motion
of the conductor in an electric motor, while the Fleming Right Hand Rule (FRH) is applied to
AC generators.
FRH aids in determining the direction of the wire's current as it moves in relation to the field.
Moving a magnet inside a coil of a wire caused an electrical current to flow through the wire,
as was observed in 1831. It is thought to be alternating voltage that is produced as the coil in
the magnetic field is rotated by a rotating magnetic field within a stationary coil because
they produce positive and negative current. Considering this, we can turn work energy into
electricity by using electrical generators.
Mutual induction, which occurs when the current in a surrounding coil change, is what
powers these electric generators. Many home appliances employ this transformer-based
technology to change the magnitude of the AC voltage. As illustrated in the diagram, a loop
that is connected to two rings attached to the end and in touch with the brushes rotates
when there is a permanent magnetic flux. The blue side slides down and the red side moves
up to cause the magnetic flux loop to rotate. Current flows through in response to changes
in the loop that connects the magnetic flux. Using Fleming's right-hand rule, we can establish
the direction of the loop; induced current is found in the direction of the middle finger's
pointing.
Why it is preferable to employ a high voltage AC generator over a low voltage turbine-driven
dynamo?
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