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Resistivity, electrical resistance of a conductor of unit cross-sectional area and unit length. A characteristic property of each material, resistivity is useful in comparing various materials on the basis of their ability to conduct electric currents. High resistivity designates poor conductors.
What do you mean by resistivity of a conductor Class 10?
Resistivity is defined as the electrical resistance of a conductor of unit cross-sectional area and unit length. The resistance of any conductor is directly proportional to the length of the conductor and inversely proportional to the area of cross-section of the conductor.
What is resistivity of a conductor Class 12?
The resistance per unit length and cross-sectional area is called resistivity. It is constant for each material. The resistivity changes from material to material. Which means it is proportional to the area of cross-section and inversely proportional to the length of the conductor.
What is resistivity with example?
For example, the resistivity of copper is generally given as: 1.72 x 10–8 Ωm. The resistivity of a particular material is measured in units of Ohm-Metres (Ωm) which is also affected by temperature. Conductivity, σ is the reciprocal of the resistivity. That is 1/ρ and has the unit of siemens per metre, S/m.
What is resistance and resistivity of a conductor?
Resistance is defined as the property of the conductor which opposes the flow of electric current. It is also defined as the ratio of the voltage applied to the electric current flowing through it. Resistivity is defined as the resistance offered by the material per unit length for unit cross-section.
What is resistivity formula?
Resistivity, commonly symbolized by the Greek letter rho, ρ, is quantitatively equal to the resistance R of a specimen such as a wire, multiplied by its cross-sectional area A, and divided by its length l; ρ = RA/l. Thus, in the metre-kilogram-second system, the unit of resistivity is ohm-metre.
What is difference between resistor and resistance?
Resistance is the property of a conductor, which determines the quantity of current that passes through it when a potential difference is applied across it. A resistor is a electrical componet with a predetermined electrical resistance, like 1 ohm, 10 ohms 100 ohms 10000 ohms etc.
On what factors resistivity depends?
The resistivity of a material depends on its nature and the temperature of the conductor, but not on its shape and size. The SI unit of electrical resistivity is the ohm-meter. Hence resistivity is dependent on the temperature.
How does resistivity change with temperature?
The general rule is resistivity increases with increasing temperature in conductors and decreases with increasing temperature in insulators. As temperature rises, the number of phonons increases and with it the likelihood that the electrons and phonons will collide. Thus when temperature goes up, resistance goes up.
What is the formula of resistance class 12?
CBSE NCERT Notes Class 12 Physics Current Electricity. Resistivity is also known as specific resistance. It is the resistance of the specific material; also it is specific to a material. R=ρ, If A and L =1 in Equation R= ρ (L/A).
What do u mean by resistivity?
Resistivity refers to the electrical resistance of a conductor of a particular unit cross-sectional area and unit length. It is definitely a characteristic property of each material. Furthermore, experts can use resistivity for comparing different materials on the basis of their ability to conduct electric currents.
What is difference between Register and resistance?
Both are different. Registers are digital sequentail devices, and resistor is a passive electronic component. Resistors are used to reduce the current flow through an electronic circuit.
What is the relation between resistivity and resistance?
For a conductor material, the resistance of the material is inversely proportional to the area of cross-section and directly proportional to the length of the conductor. Relation between Resistivity and Resistance is: R=ρlA, where ρ is the resistivity, l is the length of the conductor and A is the cross sectional area.
Is resistivity and resistance same?
Furthermore, an important difference between resistance and resistivity has to do with the flow of free electrons. Also, resistance is an aspect that opposes the flowing of free electrons. In contrast, resistivity is any material’s property that tells the resistance of the material with a particular dimension.
What is an ohm test?
This test, using a digital multimeter, determines whether: an electrical circuit is complete or broken. the resistance of a component matches the manufacturer’s specification.
What is meant by 1 ohm?
One ohm is equal to the resistance of a conductor through which a current of one ampere flows when a potential difference of one volt is applied to it.
What is current formula?
The current is the ratio of the potential difference and the resistance. It is represented as (I). The current formula is given as I = V/R. The SI unit of current is Ampere (Amp).
What is resistor in simple words?
A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses.
What is the function of resistance?
A resistor has the ability to reduce voltage and current when used in a circuit. The main function of a resistor is to limit current flow. Ohm’s law tells us that an increase in a resistors value will see a decrease in current.
Does resistivity depend on temperature?
Resistivity depends on the temperature of the material. In metal conductors, when the temperature increases, the ion cores in the metal vibrate with a larger amplitude. This hinders the flow of electrons, and the resistivity increases.
Is resistivity directly proportional to length?
The resistance of an object (i.e., a resistor ) depends on its shape and the material of which it is composed. Resistivity ρ is an intrinsic property of a material and directly proportional to the total resistance R, an extrinsic quantity that depends on the length and cross-sectional area of a resistor.
What are the 4 factors that affect resistance?
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.
On what factors resistance and resistivity depends?
Resistance of a conductor depends on length of the conductor and area of cross section of the conductor, resistivity and temperature. Resistivity is a materialistic property depends on the material and temperature of the conductor.
