Methods Of Producing EMF 030103a Flashcards
What are the six methods of creating an EMF?
Chemical
Heat
Pressure
Light (Photovoltaic)
Magnetism
Electrostatics
What does a battery consist of in its most basic form?
Two dissimilar metals and an electrolyte.
What properties of a battery control the voltage of the battery?
The type of metals and electrolytes used.
A phenomenon in which a temperature difference between two dissimilar metals produces a voltage difference between them is known as what?
Seebeck Effect
What source is extremely useful in heating controls where it is used as a sensor or a power source for relays?
Thermocouples (Heat EMF source)
What is it called when certain materials have pressure applied to them and they generate a voltage?
Piezoelectricity
Piezoelectric materials can be classified in what two main groups?
Crystals and Ceramics. The best-known material is quartz.
Where electrons are dislodged from atoms under the influence of light is known as?
The photoelectric effect.
What are the advantages of solar cells?
No moving parts
No noise
No waste products or pollution
Have a very long life span.
What is the process called when a conductor is moved through a magnetic flux?
Electromagnetic Induction or Generator Action.
What law states that the magnitude of the voltage induced in a conductor is proportional to the rate at which the conductor cuts the lines of force?
Faraday’s Law Of Induction.
How many lines of force need to be cut by a conductor per second to induce one volt?
100 million lines per second = 1 volt
What 3 factors affect the value of induced voltage?
Flux density or strength of the field.
The length of the conductor within the field.
The rate at which lines of force are cut by the conductor.
What are 3 methods in which the mechanical rotation for generators can be produced?
Wind
Falling Water
Steam Driven Turbines
An electric process in which certain materials become electrically charged after they are separated from a different material in which they were in contact.
Tribocharging
