What is Ohm's law? Explain how it is used to define the unit of resistance.
Answers
Answer:
Ohm's Law is the mathematical relationship among electric current, resistance and voltage. The principle is named after the German scientist Georg Simon Ohm.
In direct-current (DC) circuits, Ohm's Law is simple and linear. Suppose a resistance having a value of R ohms carries a current of I amperes. Then the voltage across the resistor is equal to the product IR. There are two corollaries. If a DC power source providing E volts is placed across a resistance of R ohms, then the current through the resistance is equal to E/R amperes. Also, in a DC circuit, if E volts appear across a component that carries I amperes, then the resistance of that component is equal to E/I ohms.
Mathematically, Ohm's Law for DC circuits can be stated as three equations:
E = IR
I = E/R
R = E/I
When making calculations, compatible units must be used. If the units are other than ohms (for resistance), amperes (for current), and volts for voltage), then unit conversions should be made before calculations are done. For example, kilohms should be converted to ohms, and microamperes should be converted to amperes.
Answer:
V / I = Constant = R. V = IR. Here R is the resistance. The unit of resistance is ohm (Ω). One ohm (Ω) is the resistance of a conductor when a potential difference of one volt is applied to its ends and a current of one ampere flows through it..
Ohm’s Law: The ratio of potential difference between the ends of a conductor to the current flowing through the conductor is a constant. This constant is defined as Resistance of the conductor.
Explanation:
According to the ohm's law the current flowing through a conductor is directly proportional to the potential difference applied across its end only when the physical condition like temperature and pressure remain constant.
to the ohm's law the current flowing through a conductor is directly proportional to the potential difference applied across its end only when the physical condition like temperature and pressure remain constant.V = IR. { where R is proportionality constant} unit of R is ohm .
According to Ohm's Law,
The flow of current is directly proportional to the potential difference applied at its ends provided that temperature and physical conditions are constant.
So V is directly proportional to I
or V = IR
Where R is constant of proportionality, which is called resistance.
Unit of V is Volt(V) and that of Current is Ampere(A).
Hence from relation V = IR,
R = V/I
So unit of R is V/A, which is called Ohm.
1ohm is the unit of resistance . It is equal to 1 volt upon 1 ampere. It means that an object having a resistance of 1ohm allows 1 ampere of current to flow through 2 points having potential difference of 1 volt.
A resistor reduces (or resists) the flow of current. The value of the resistance is expressed as a number of ohms (the symbol Ω is used for ''ohm''). ... So, a 1k Ω resistor has a value of 1,000 ohms and the number we will code is 1,000.
