Physical voltage, resistance, current, voltmeter, question, kneel and beg。。。。。。。。。。。

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The Department of Electricity is divided into tombs

1. The strength of the current bucket letter.

i q power t

2. Resistance: r= l s

3. Ohm's law.

i u r4, Joule's law:

1) Q i2RT universal formula).

2), Q uit pt uq power u2t r (pure resistance formula) 5, series circuit:

1）、i＝i1＝i2

2）、u＝u1＋u2

3), R R1 R2 (1), W uit pt uq (universal formula) 2), W i2rt u2t r (pure resistance formula) 6, parallel circuit:

1）、i＝i1＋i2

2）、u＝u1＝u2

r 1 r1 1 r2 [ r r1r2 (r1 r2)]4), i1 i2 r2 r1 (shunt formula).

5）、p1/p2＝r2/r1

7. Constant Resistance:

1) Ruler pin, i1 i2 u1 u2

2）、p1/p2＝i12/i22

3）、p1/p2＝u12/u22

8 electrical power: 1), w uit pt uq (universal formula) 2), w i2rt u2t r (pure resistance formula) 9 electrical power: 1), p w t ui (universal formula) 2), p i2r u2 r (pure resistance formula).

The voltage between ab is . In this circuit, the constant current source current is 3A, the A branch resistance is 6 3 9, and the B branch resistance is 3 6 9. The resistance of the two branches is equal, so the current of each branch is divided into half, that is, the current of each branch is, then the voltage drop on the resistor of 3 is 9V, and the voltage drop on the resistor of 6 is 9V.

Since the direction of the current in the branch is to the right, the voltage drop on the resistor is positive and negative on the left. Taking the common point at the right end as the reference point, then the voltage drop on the resistor of point A on branch A is actually 3, and the voltage drop on the resistor of point B on branch B is 9V. Then uab=ua-ub=.

Or do it this way, with the rightmost end as the reference point. 3A is the current source in the circuit. The total resistance of the circuit is r total ra rb=(6+3) (3+6)=, where ra is the total resistance of the upper branch and rb is the total resistance of the lower branch.

The voltage at the power supply end is the total voltage of U Total IXR Total . Similarly, the resistor series divider principle, the voltage at point A is UX3 (6+3) = the point voltage is UX6 (3+6)=.

Current, voltage, resistance.

The conversion formula is mainly derived from Ohm's law r=u i and w=uit, so try to derive it yourself.

1. There are the following rules for the current and voltage of the series circuit: (e.g., R1, R2) Current:

i=i1=i2 (the current is equal everywhere in the series circuit) Voltage: u=u1+u2 (the total voltage is equal to the sum of the voltages everywhere) Resistance: r=r1+r2 (the total resistance is equal to the sum of the resistors) If n resistors with the same resistance value are connected in series, then there is r total = nr

2. The current and voltage of parallel circuit have the following rules: (such as: R1, R2 in parallel) Current: i=i1+i2 (the main circuit current is equal to the sum of the currents of each branch) Voltage: u=u1=u2 (the main circuit voltage is equal to the voltage of each branch) Resistance:

The reciprocal of the total resistance is equal to the reciprocal sum of the various parallel resistors) or.

If n resistors with the same resistance value are connected in parallel, then there is r total =

Attention: The total resistance of a parallel circuit is smaller than that of any one branch.

The formula for calculating electrical work is: w=uit (unit w joule (j); u volts (v); i Ann (a); t seconds).

5. When using w=uit to calculate electrical work, pay attention to the following: w, u, i and t in the formula are in the same circuit section; The unit of calculation should be unified; Any three quantities known can be found to be a fourth quantity.

6. The following formula can also be used to calculate electrical work: w=i2rt

w=pt；w=uq (q is the amount of electricity); [Electricity.

Part] 1 Current intensity: i q power t

2. Resistance: r= l s

3 Ohm's law: i u r

4 Joule's Law:

Q i2RT Universal Formula).

q uit pt uq power u2t r

Pure resistance formula).

5 series circuits:

i＝i1＝i2

u＝u1＋u2

r＝r1＋r2

u1/u2＝r1/r2

Partial pressure formula) p1 p2 r1 r2

6 parallel circuits:

i＝i1＋i2

u＝u1＝u2

1/r＝1/r1＋1/r2

r＝r1r2/(r1＋r2)]

i1 i2 r2 r1 (shunt formula).

p1/p2＝r2/r1

7. Constant Resistance:

i1/i2＝u1/u2

p1/p2＝i12/i22

p1/p2＝u12/u22

8. Electric power: w uit pt uq

Universal formula) w i 2rt u 2t r

Pure resistance formula).

9. Electric power: P W T UI

Universal formula) p i2 r u 2 r

Pure resistance formula).

1. Current intensity: i q power t

2. Resistance: r= l s

3 Ohm's law: i u r

4 Joule's Law:

Q i2RT Universal Formula).

q uit pt uq power u2t r

Pure resistance formula).

5 series circuits:

i＝i1＝i2

u＝u1＋u2

r＝r1＋r2

u1/u2＝r1/r2

Partial pressure formula) p1 p2 r1 r2

6 parallel circuits:

i＝i1＋i2

u＝u1＝u2

1/r＝1/r1＋1/r2

r＝r1r2/(r1＋r2)]

i1 i2 r2 r1 (shunt formula).

p1/p2＝r2/r1

7. Constant Resistance:

i1/i2＝u1/u2

p1/p2＝i12/i22

p1/p2＝u12/u22

8. Electric power: w uit pt uq

Universal formula) w i 2rt u 2t r

Pure resistance formula).

9. Electric power: P W T UI

Universal formula) p i2 r u 2 r

Pure resistance formula).

I'm exhausted!!

Ohm's law: The current in a conductor is directly proportional to the voltage across the conductor and inversely proportional to the resistance of the conductor. If u denotes the voltage applied to the conductor, r denotes the resistance of the conductor, and i denotes the current in the conductor, then Ohm's law can be written as follows: i=

The units of i, u, and r in the u r formula are amperes, volts, and ohms, respectively.

To measure a relatively small current (below 10A), the multimeter can be adjusted to the current level, and then connected in series in the circuit; A clamp ammeter is used to measure large currents (10 A or more) by placing the measuring clamp of the clamp ammeter on the wire.

Electrical formulas and basic laws.

1. Characteristics of series and parallel connection (two circuits):

1.Tandem:

The currents are equal everywhere. i=i

The voltage of 1=i2 is equal to the sum of the voltages of each electrical appliance. u=

The total resistance in the U1+U2 series circuit is equal to the sum of the resistances of each electrical appliance.

r, total r1+r2

Voltage distribution law:

Electrical power (electric work) distribution law:

2.Parallel: The voltage of the parallel circuit is equal. u=

u1=u2②

The parallel circuit trunk current is equal to the sum of the currents of each branch. i=i1+i2

The reciprocal of the total resistance in a parallel circuit is equal to the sum of the reciprocals of each resistor.

Current Distribution Rules:

Electrical power (electric work) distribution law:

2. The Law of Two Laws:

1 Ohm's Law: i=

Two deformation formulas.

Principle of resistance measurement).

Definition of current intensity: i=

q: electricity)2 Joule's law: q=

i2RTQ: heat).

3. Electric power and electric power

1.Electric work: 2Electrical power.

Note: Where the formula contains r, it is only applicable to pure resistive circuits. The heat of a non-pure resistive circuit can only be obtained using Joule's law q=i2rt.

Ohm's Law.

The voltages are equal everywhere in the parallel circuit, and the total current is equal to the sum of the currents of the branches.

The current is equal everywhere in the series circuit, and the total voltage is equal to the sum of the voltages of the branches.

For the sake of mm.

1.Two tables in parallel.

The voltages at both ends of the 3 devices are equal and set to u

u=60v=i*r

Voltmeter current i=U voltmeter resistance r=60 3k=1 50ai*(ammeter resistance r+r1)=u=60===r+r1=60 ===r1=300-10=290 ohms.

That's the real value.

The measured value is to see the two tables as ideal, then.

r=u i=60 euros are enviable.

That's what you measure.

2.Both sides are connected in series.

In this case, the voltage of the two stages of the voltmeter and the voltage of the two stages of the resistor are equal.

U=60V, voltmeter current, i=60, voltmeter resistance, r=1, 50A, then resistive current i'=

r2=u/i'= Euros.

That's the real value of real potato farming.

The measured value is to see the two tables as ideal, then.

r2=60 ohms.

That's what you measure.

Well, that's it

1.After the desktop computer is used for a period of time, in order to ensure the stability of the computer, you need to open the main chassis cover to remove dust, this is because the cooling fan is the fan blade that rubs with the air during the rotation process, and the static electricity can attract light and small objects, so the dust will adhere to the fan blade.

5.If the glass rod is in contact with the metal ball of the electroscope that is not charged, the metal foil of the electroscope will be opened, and the reason why the metal foil is opened is that the metal foil has a negative charge, and the same charge repels each other. __

24.In order to improve the accuracy of the measurement, the influence of the ammeter connection on the original circuit should be negligible, therefore, the internal resistance of the ammeter should be small

I hope it helps you, and if you have any questions, you can ask them

I wish you progress in your studies and go to the next level! (*

Electrical Section].

1. Current intensity: i q power t

2. Resistance: r= l s

: resistivity (m), l: length of the conductor (m), s: cross-sectional area of the conductor (m2)}

3 Ohm's law: i u r

4 Joule's Law:

1) Q i2RT universal formula).

2) Q UIT PT UQ power u2t r (pure resistance formula).

5 series circuits:

1）、i＝i1＝i2

2）、u＝u1＋u2

3）、r＝r1＋r2

4）、u1/u2＝r1/r2

Partial pressure formula) 5), p1 p2 r1 r2

6 parallel circuits:

1）、i＝i1＋i2

2）、u＝u1＝u2

r＝1/r1＋1/r2

r＝r1r2/(r1＋r2)]

4), i1 i2 r2 r1 (shunt formula) (5), p1 p2 r2 r1

7. Constant Resistance:

1）、i1/i2＝u1/u2

2）、p1/p2＝i12/i22

3）、p1/p2＝u12/u22

8 electrical work: 1), w uit pt uq

Universal formula) 2), w i2rt u2t r

Pure resistance formula).

9. Electric power: 1), P W T UI

Universal formula) 2), p i2r u2 r

Pure resistance formula).

1. Ohm's Law Part.

1 i = u r (Ohm's law: the current in a conductor is proportional to the voltage across the conductor and inversely proportional to the resistance of the conductor).

2．i=i1=i2=…=in

The characteristics of the current in the series circuit: the current is equal everywhere).

3．u=u1+u2+…+un

Characteristics of the voltage in the series circuit: In the series circuit, the total voltage is equal to the sum of the voltages at both ends of the circuit of each part).

4．i=i1+i2+…+in

Characteristics of the current in the parallel circuit: the current on the main circuit is equal to the sum of the currents of each branch).

5．u=u1=u2=…=un

The characteristics of the voltage in the parallel circuit: the voltage at both ends of each branch is equal. are equal to the supply voltage).

6．r=r1+r2+…+rn

Characteristics of resistance in series circuits: the total resistance is equal to the sum of the resistances of the circuit parts).

7．1/r=1/r1+1/r2+…+1/rn

Characteristics of the resistors in parallel circuits: the reciprocal of the total resistance is equal to the sum of the reciprocals of each parallel resistor).

8 r and = r n (the formula for finding the total resistance when n of the same resistor in parallel).

9 r string = nr

The formula for finding the total resistance when n identical resistors are connected in series).

10．u1：u2=r1：r2

The relationship between voltage and resistance in a series circuit: the ratio of voltage is equal to the ratio of resistance to which they correspond).

11．i1：i2=r2：r1

The relationship between current and resistance in parallel circuits: the ratio of current is equal to the inverse ratio of the resistance to which they correspond).

Second, the electric power part.

12．p=ui

Empirical, suitable for any circuit).

13．p=w/t

defined, suitable for any circuit).

14．q=i2rt

Joule's law, suitable for any circuit).

15．p=p1+p2+…+pn

Suitable for any circuit).

16．w=uit

Empirical, suitable for any circuit).

composite formula, suitable only for purely resistive circuits).

composite formula, suitable only for purely resistive circuits).

Empirical, only suitable for purely resistive circuits. where w is the work done by the current flowing through the conductor and q is the heat produced by the current flowing through the conductor).

composite formula, suitable only for purely resistive circuits).

composite formula, suitable only for purely resistive circuits).

22．p1:p2=u1:u2=r1:r2

The relationship between electrical power and voltage and resistance in series circuits: In series circuits, the ratio of electrical power is equal to the ratio of voltage and resistance corresponding to them).

23．p1:p2=i1:i2=r2:r1

The relationship between electrical power and current and resistance in parallel circuits: In parallel circuits, the ratio of electrical power is equal to the ratio of the current corresponding to them and equal to the inverse ratio of the resistance they correspond).