What is the formula for Ohm s law and what is the formula for Ohm s law?

Ohm's law is a fundamental law that expresses the relationship between current, voltage (or potential), and resistance in a circuit.

1) Ohm's law for partial circuits.

The current (i) through the conductor is directly proportional to the voltage (u) across the conductor and inversely proportional to the resistance (r) of the conductor, i=u r

Transform the above equation to.

u=irr=u i(2) Ohm's law for all circuits.

The current in the closed circuit is directly proportional to the electromotive force of the power supply and inversely proportional to the sum of the load resistance and the internal resistance of the power supply in the circuit, i.e.

where i – the current flowing through the circuit in amperes (a);

e - power electromotive force, in volts (v);

r – load resistance in ohms ( ).

r – the internal resistance of the power supply, in ohms ( ).

If you want to consider the resistance of the connected wires, add the resistance value of the wires to the total resistance.

Ohm's law: In the same circuit, the current through the conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance value of the conductor, which is Ohm's law, and the basic formula is i=u r. Ohm's law was proposed by George Simon Ohm, and in honor of his contribution to electromagnetism, the physics community named the unit of resistance Ohm, which is represented by symbols.

Resistance. Basic unit: ohm, abbreviated as ohm, symbol

Conversion unit: kiloohm (k), megaohm (m), gieum (g) Conversion value: 1000 ohms 1 thousand ohms.

1000 kohms 1 trillion ohms.

1000 megaohms 1 gigaoh.

Voltage. Basic unit: volt, abbreviated volt, symbol v

Conversion unit: kilovolt (kv), millivolt (mv), microvolt (v) conversion value: 1 thousand volts 1000 volts.

1 volt 1000 mV 1000000 microvolts.

Current. Basic unit: ampere, abbreviated ampere, symbol a

Conversion unit: kiloamperes (ka), milliamperes (ma), microamperes (a) conversion value: 1 thousand amperes 1000 amps.

1 amp 1000 mA 1000000 μA.

Electrical power. The physical quantity that indicates how fast or slow the electrical energy is consumed, and the power of an electrical appliance is equal to the electrical energy it consumes in 1 second.

Unit watt referred to as watt unit symbol w (is lowercase w, uppercase is the symbol of electrical energy) commonly used units are milliwatts (mw), kilowatts (kw), their conversion relationship with w is: 1 w = 1000 mw; 1kw=1000w

Electrical energy Electrical energy is a physical quantity that indicates how much work an electric current does.

The unit joule is referred to as the coul, and the unit symbol is w

kWh, yes"degrees"The scientific name of . The symbol is kw·h; The more commonly used unit is the joule, abbreviated as "joule" and the symbol for "joule" is j).

Electrical energy conversion: 1kw·h=

Ohm's law u=ir

That is, voltage = resistance multiplied by current.

When the voltage is constant: the resistance is inversely proportional to the current.

When the resistance is constant: the voltage is proportional to the current.

Note (Not the other way around.)

For example, the resistance is inversely proportional to the current because the voltage is constant. Because the resistance of the resistor is immutable!

The deformation formula is i=u r r=u i

The formula for electrical power.

p=ui w=pt

That is, electrical power = current times voltage.

Electrical energy = electrical power multiplied by time.

Deformation formula. i=p/u

u=p ip=u divided by the square of r

p = i squared times r

t=w/pp=w/t

Formulas in series circuits.

i total = i1 = i2

u total = u1 + u2

r total = r1 + r2

r1：r2=u1：u2

p1：p2=r1：r2

in parallel circuits.

u total = u1 + u2

i total = i1 = i2

rTotal 1=r1 1+r2 1

r total = (r1+r2) (r1 times r2).

p1；p2=r2：r1

Formula: i=u r.

Derived from Ohm's law i=u r or u=ir cannot say that the resistance of a conductor is proportional to the voltage at its ends and inversely proportional to the current passing through it.

Because the resistance of a conductor is a property of itself, depending on the length of the conductor, cross-sectional area, material and temperature, humidity, even if there is no voltage at both ends of it, no current passes through it, its resistance value is also a fixed value.

History

Ohm's first phase of experiments was on the attenuation of the electromagnetic force produced by an electric current as a function of wire length, the results of which were published in his first scientific paper in May 1825.

In this experiment, he encountered difficulties in measuring the intensity of the electric current. Inspired by the galvanometer invented by the German scientist Schweiger, he combined Oster's discovery of the magnetic effect of electric current with the Coulomb torsion scale method to design a current torsion scale and use it to measure the intensity of electric current.

Ohms are emitted from preliminary experiments and the electromagnetic force of an electric current is related to the length of the conductor. There is no direct connection between the relation and today's Ohm's law representation. Ohm also did not relate the three quantities of electric potential difference (or electromotive force), current intensity, and resistance at the time.

Before ohms, there was no concept of resistance, but the conductivity (conductivity) of metals had already been studied. In July 1825, Ohm also studied the relative conductivity of metals using the apparatus used in the preliminary experiments described above. He measured wires of the same diameter from various metals and determined the relative conductivity of metals such as gold, silver, zinc, brass, and iron.

Although the experiment was crude and error-prone, Ohm decided to study it as a major observational measure in the next experiment, thinking that the fact that the current was constant throughout the wire, suggesting that the current intensity could be an important fundamental quantity for the circuit.

The formula for Ohm's law is i=u r.

Ohm's law is simply described as follows: In the same circuit, the current through a conductor is proportional to the voltage across the conductor and inversely proportional to the resistance of the conductor. This law was proposed by the German physicist Georg Simon Ohm in his book "Determination of the Law of Conductivity of Metals" published in April 1826.

As the work on circuits progressed, the importance of Ohm's law was gradually recognized, and Ohm's reputation increased greatly. In honor of Ohm's contribution to electromagnetism, the physics community named the unit of resistance Ohm, which is represented by symbols.

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What are the formulas of Ohm's law?

Definitions

Ohm's law states that in the same circuit, the current passing through a sliding mode conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the signal-bearing conductor.

Formula

Ohm's law is divided into two types, one is called Ohm's law for partial circuits, and the other is Ohm's law for full circuits (Ohm's law for closed circuits).

Ohm's law formula for partial circuits: i=u r

Wherein: i, u, r - the three quantities are the current intensity, voltage and resistance at the same time in the same part of the circuit.

The formula is derived from Ohm's law:

Parallel circuit: series circuit.

i total = i1 + i2 i total = i1 = i2

u total = u1 = u2 u total = u1 + u2

1:r total = 1:r1+1:r2 r total = r1+r2r

i1：i2=r2：r1 u1：u2=r1：r2

r total = r1 + r2: r1r2

r total = r1r2r3: r1r2 + r2r3 + r1r3

That is: current = voltage divided by resistance.

Or resistance multiplied by current = voltage.

Remember that resistance and voltage are the bosses. There can be no confusion.

Ohm's law for full circuits (Ohm's law for closed circuits) formula: i=e (r+r).

where E is the electromotive force, R is the internal resistance of the power supply, the internal voltage U = IR, E = U inside + U outside.

Scope of application: pure resistive circuit.

Energy conversion in a closed circuit:

e=u+ir

ei=ui+i^2r

p release = ei

p output = ui

Pure resistive circuits.

p output = i 2r

e^2r/（r+r）^2

e^2/（r^2+2r+r^2/r）

When r=r, p output is maximum, and p output=e 2 4r

mean inequality).

Ohm's trapped beam law is one of the fundamental laws in electricity that describes the relationship between current, voltage, and resistance. The formula is: v = IR where v is the voltage in volts (V); i represents the current in amperes (a); r denotes the resistance in ohms ( ) This calendar formula illustrates that in a circuit, voltage is proportional to current and current is inversely proportional to resistance.

That is, when the resistance is constant, the change in voltage and current is proportional; When the voltage is constant, the change in current and resistance is inversely proportional. Ohm's law is an important fundamental law in electricity, which is widely used in circuit design, electronic engineering, power system and other fields.

Ohm's Law formula: i=u r.

i is the current, the unit is amperes, and the symbol is a; u is the voltage, the unit is volts, and the symbol is v; r is the resistance, the unit is ohms, and the symbol is .

Introduction: In the same circuit, the current in the conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the conductor, which is Ohm's law. Ohm's Law formula: i=u r.

Note: The derivation of Ohm's law i=u r r=u i or u=ir cannot say that the resistance of a conductor is directly proportional to the voltage at both ends and inversely proportional to the current passing through it, because the resistance of a conductor is a property of itself, depending on the length, cross-sectional area, material and temperature, humidity of the conductor, even if there is no voltage at both ends of it, no current passes through, its resistance value is a fixed value.

Ohm's law can be written as follows: i = u r. The units of i, u, and r in the formula are amperes, volts, and ohms, respectively.