Electrical resistance is analogous to friction in a mechanical system. Friction, like resistance, converts energy to heat and dissipates it to the surrounding environment. … When enough current is impeded (i.e. resisted) this energy can even be converted directly into light which reduces the current flow.
What does electrical resistance depend on?
The resistance of a wire is directly proportional to its length and inversely proportional to its cross-sectional area. Resistance also depends on the material of the conductor. … The resistance of a conductor, or circuit element, generally increases with increasing temperature.
What 3 things does electrical resistance depend on?
The resistance of a given piece of wire depends of three factors: the length of the wire, the cross-sectional area of the wire, and the resistivity of the material composing the wire. To understand how this works, think of water flowing through a hose.
Why is electrical resistance important?
Resistance is another important property that can be measured in electrical systems. … The same is true with electricity. Materials with low resistance let electricity flow easily. Materials with higher resistance require more voltage (EMF) to make the electricity flow.
What are the four factors that can increase resistance in a circuit?
There are 4 different factors which affect resistance:
- The type of material of which the resistor is made.
- The length of the resistor.
- The thickness of the resistor.
- The temperature of the conductor.
Does resistance depend on voltage?
The voltage is constant and doesn’t depend on the resistance that happens to be in the way.
Which of the following will increase the resistance of wire?
Increasing the resistivity of the material the wire is composed of will increase the resistance of the wire. Increasing the cross-sectional area of the wire will increase the resistance of the wire. Increasing the length of the wire will increase the resistance of the wire.
What is the relationship between resistance and current?
The relationship between current, voltage and resistance is expressed by Ohm’s Law. This states that the current flowing in a circuit is directly proportional to the applied voltage and inversely proportional to the resistance of the circuit, provided the temperature remains constant.
Which change decreases the resistance of a piece of copper wire?
Resistance decreases as copper (or any other metal) is cooled. Its atoms vibrate less, and so they impede the flow of electrons less. Pure copper has less resistance than copper containing impurities. Impurity atoms are a different size to copper atoms, so they get in the way of moving electrons.
How do you get rid of electrical resistance?
Of course there exist many different ways to reduce the resistance, such as using a thicker wire (increase the cross section area), lowering the temperature, or even changing the material.
Why do we use resistance?
Resistance in any electric wire helps in manipulating the current that is flowing through the circuit. … Furthermore it sometimes helps in saving electric appliances from excess current as the excess current would produce greater heat in the presence of resistance leading to breakdown of circuit at that point.
Is electrical resistance due to friction?
Resistance is similar to friction for electrical energy; resistance causes the electrical energy to be lost as heat (thermal energy), just like friction causes mechanical energy to be lost as heat. Resistance is a measure of how much voltage an electrical element needs in order to increase the electric current.
What factor does not affect resistance?
The resistance of a conductor does not depend on Pressure.
So it depends on the material. It is inversely proportional to the cross-sectional area of the wire. The r esistance is directly proportional to the length of the wire and resistivity of the material used in making the wire.
How does changing the length of wire affect the resistance?
First, the total length of the wires will affect the amount of resistance. The longer the wire, the more resistance that there will be. … Second, the cross-sectional area of the wires will affect the amount of resistance. Wider wires have a greater cross-sectional area.