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When the electric train is moving down a hill the DC motor acts as?
Wiki User
∙ 7y ago
The DC motor acts as a generator. The electricity generated can be used to power the overhead (or third rail) line and used by other trains going up a hill, thus acting as a brake slowing the train going downhill.
Wiki User
∙ 7y ago
Anonymous
shunt motor
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What does a commutater in an electric motor do?
It (1) provides a means of connecting a rotating coil to the external circuit, and (2) it is a rotating switch which ensures that the direction of the current through the coil always acts in the same direction relative to the magnetic field in order to ensure its torque acts in the same direction.
How does the 3-phase induction motor acts like 2-phase induction motor if a phase is disconnected from supply?
yes the motor will run but will draw more current and the torque will be not constant means not smooth due to unbalanced current
How are coil in a motor and the coil in an electromagnet the same?
All (electrical) coils are the same, in that they are coils. All coils honor the same principles: investing electrical energy into a coil results in a magnetic field. Investing magnetic energy into a coil results in an electric current. But, different coils serve different purposes. For example, a coil in an electromagnet is used to magnify the magnetic field surrounding a wire that carries an electric current. This is typically aided by supplying a core made from a a ferromagnetic material; that is, a material which offers very little resistance to magnetism. In an electromagnet, the coil and its core is typically stationary (even though the entire contraption might move, as is the case with a crane at the scrapyard). Therefore, the coil in an electromagnet converts electrical energy into magnetic energy. The reversal of this process converts magnetic energy into electric energy, through a process known as induction. This is the case in dynamos, electric generators, and also in some electric motors. Some machines make use only of the conversion from electric to magnetic energy, as is the case with the electro magnet. This group includes some forms of electric motors and generators. Some machines make use only of the conversion from magnetic to electric energy, as is the case in the coil used to provide the ignition spark used with combustion engines. Some machines make use of both effects. This includes transformers, and many forms of electric generators and motors. For example, a stationary coil in an electric motor might supply a magnetic field which acts on the rotor. If the field in the stationary magnet itself rotates, as is for example the case with 3-phase electric power systems, this rotating magnetic field induces an electric current in the rotor. The rotor could itself be a coil, which in response to this induced current creates a magnetic field, pulled around by the rotating field of the stationary part. (This is in fact the principle behind the most common electrical motor, the short-circuit motor) Further uses of coils include that of (transient) energy storage: an electric current can build a magnetic field. When the current changes, the magnetic field also changes, and thus induces an electric current. This form of coils is frequently used in electronics to create filters; devices that suppress or select electric current according to its frequency. For example, your HiFi's loudspeakers contain a filter device that divides the electric signal from your amplifier into the higher frequency portions fit for your tweeter, and the lower frequency portions fit for your bass speaker.
Does the alternating current supplied to the armature winding of a DC motor gets converted to dc by a commutator before it flows through the armature coil of the DC motor?
The commutator is a rotating switch, which reverse the polarity of the generated voltage every half-cycle. So it acts to rectify the output voltage.
What are the simple machines in a forklift?
There are gears in the motor and engine. The tires are connected to a wheel and axle, so is the steering wheel. The actual forklift acts as a lever. The tips of the fork are actually wedges, but that is irrelavent.
Do all magnets have a force that acts on moving electric charges?
yes,they do
A split metal ring that acts as a switch in an electric motor is called a?
commutator
How electric current have magnetic effect?
The magnetic force acts only on moving electric charges; A constant electric current produces an unchanging magnetic field and a changing electric current produces a changing magnetic field.
What makes up the magentic field?
Magnetic fields are made up by a moving electric charge within which the force of magnetism acts:)
How does a standing fan work?
With an electric motor. A force acts on an electric current when it runs through a magnetic field (called the Lorentz Force) see: http://en.wikipedia.org/wiki/Electric_motor
CENTRIPETAL?
A force that acts on a body moving in a circular path and is directed around the object which the body is moving
Why must the direction of the current in a motors electromagnets be switched repeatedly?
The magnetism set up in the motor, attracts opposite poles. One pole is in the rotor and the the other on the stator. The attraction causes the rotor to turn. If allowed to continue, the pole will get as close as possible and then stop. The motor will stall. On a brushed, DC motor, the commutator acts as a switch and turns off the nearest coils and connects the next one along, allowing continuous rotation. On an AC motor, the supply is changing direction, this acts in synchronization with the rotation.
Why is it necessary to change the directions of the current in the coil of an electric motor as it turns?
The magnetism set up in the motor, attracts opposite poles. One pole is in the rotor and the the other on the stator. The attraction causes the rotor to turn. If allowed to continue, the pole will get as close as possible and then stop. The motor will stall. On a brushed, DC motor, the commutator acts as a switch and turns off the nearest coils and connects the next one along, allowing continuous rotation. On an AC motor, the supply is changing direction, this acts in synchronization with the rotation.
What is the enzyme that acts as a motor - generating the energy currency of the cell?
ATP is the enzyme that acts as the motor for the cell. ATP generates the energy currency of the cell.
Can a motor operate as generator?
Yes, by giving mechanical power to motor . It acts as a Generator.
Friction that acts on objects that are not moving?
Static Friction
What does a commutater in an electric motor do?
It (1) provides a means of connecting a rotating coil to the external circuit, and (2) it is a rotating switch which ensures that the direction of the current through the coil always acts in the same direction relative to the magnetic field in order to ensure its torque acts in the same direction.
