Resistance is the opposition to flow or movement.
Resistance in a a mechanical system could be friction, wind, gravity.
Resistance can be opposition to a policy, or to an invasion (e.g. French Resistance).
Resistance in an electrical circuit is the limiting or opposition to current flow. It is measured in Ohms.
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Electrical Resistance
The technical definition is "Electrical resistance is a ratio of the degree to which an object opposes an electric current through it, measured in ohms."
In simplfied terms, electrical resistance is broadly equivalent to friction in a mechanical system. If you applied a voltage to a circuit with zero resistance then you would get an infinite current. In reality all circuits have some resistance which limits the current.
We can predict the current in a given circuit using Ohms law:
V = I x R
Where:
V is Voltage (measured in Volts)
I is current (measured in Amps)
R is resistance (measured in Ohms)
You will often see this in the form E = I x R. It is exactly the same thing, just a different convention where "E" is used for voltage instead of "V"
Ohms law is:
V=I/R
V=Voltage (volts)
I=Current (amps)
R=Resistance (Ohms)
Resistance in an AC circuit is called Impedance (Z)
Electrical resistance is the amount that an object opposes electrical current. All things being equal (temperature, purity, etc.), resistance is a function of both its physical geometry and the resistivity of the material it is made from. Impurities in materials and fluctuation of temperature can effect the amount of resistance a material will exhibit.
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Electrical resistance is the amount that an object opposes electrical current. All things being equal (temperature, purity, etc.), resistance is a function of both its physical geometry and the resistivity of the material it is made from. Impurities in materials and fluctuation of temperature can effect the amount of resistance a material will exhibit.
There are many different types of resistance, and I recommend that for starters you read up on the Wikipedia article on electrical resistance.
http://en.wikipedia.org/wiki/Electrical_resistance
Superconductors have no resistance. Conductors have low resistance, semiconductors have intermediate resistance, and insulators have high resistance.
The resistance arm of a lever is the distance between the fulcrum (pivot point) and the point where the resistance force is applied. It determines the amount of force required to move the resistance, with a longer resistance arm requiring less force to overcome a given resistance.
A high-resistance bulb typically has a thicker filament compared to a low-resistance bulb. The thicker filament in a high-resistance bulb can withstand the greater heat generated by the increased resistance, resulting in a longer lifespan for the bulb.
The resistance of a wire is directly proportional to its length, so doubling the length will also double the resistance. Therefore, doubling the 4 ohm resistance wire will result in a new resistance of 8 ohms.
Inertia.
B - Dynamic resistance
The different types of resistance available on exercise bikes are magnetic resistance, air resistance, and friction resistance. Magnetic resistance uses magnets to create resistance, air resistance uses air to create resistance, and friction resistance uses a brake pad to create resistance.
Resistance is resistance , no matter if it is contact resistance or any other resistance. And formula is R = V / I.
abrasion resistance is the resistance in abrasion
The theoretical resistance simply defines what resistance is while practical resistance refers to putting the theoretical resistance into action.
Superconductors have no resistance. Conductors have low resistance, semiconductors have intermediate resistance, and insulators have high resistance.
Corrosion Resistance
zener resistance of a zener diode is the resistance of the zener diode but which is the resistance of a diode
On Circuit Resistance = Close to the total load Resistance. Off Circuit Resistance = Near Infinitive High Resistance.
Energy is gradually lost, through air resistance, and resistance in the string.Energy is gradually lost, through air resistance, and resistance in the string.Energy is gradually lost, through air resistance, and resistance in the string.Energy is gradually lost, through air resistance, and resistance in the string.
this are those resistance hos values can not be changed under this categoric tow types of resistance. 1.carbon resistance. 2.whire wound resistance.
output resistance decreases and input resistance increases