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When Kirchhoff's law is used, how many branches are there and how many nodes are there
For specific circuits, starting from 1, theoretically more or less possible
Is voltmeter a branch in Kirchhoff's law circuit analysis?
If the internal resistance of the voltmeter can be regarded as infinite, don't worry about it
If it can't be regarded as infinity, calculate the current
Examples of Kirchhoff's law
It's better to explain in detail, so it's easy to understand
Kirchhoff's current law [1] (KCl) the algebraic sum of all the currents flowing out (into) any node in any lumped parameter circuit at any instant is always zero, that is, in terms of the reference direction, the current flowing out of the node takes a positive sign in the formula, Kirchhoff current law is the embodiment of current continuity and charge conservation law in circuit. It can be applied to any imaginary closed surface of circuit
Kirchhoff's law of voltage (KVL) in any circuit with lumped parameters, the algebraic sum of the voltages along each section of the circuit is always zero at any moment, that is, when the reference direction of the voltage is the same as the detour direction of the circuit, the voltage takes a positive sign in the formula, Kirchhoff's law of voltage is the embodiment of the law of conservation of energy and the law of single value of potential in the circuit. It can be extended to the imaginary circuit
It's a simple law,
The first is that the current flowing in is equal to the current flowing out
The second is that the total voltage of each component in the closed circuit is equal to 0
RELATED INFORMATIONS
- 1. What is the reason for the error in the verification experiment of Kirchhoff's voltage and current law?
- 2. Understanding of Kirchhoff's law most urgent!
- 3. Kirchhoff's law experiment 1. According to the circuit parameters in Figure 2-1, calculate the current I1, I2, I3 to be measured and the voltage value on each resistance, and record them in the table In order to select the range of milliammeter and voltmeter correctly 2. In the experiment, if the current of each branch is measured by the direct current milliampere range of the pointer multimeter, under what circumstances may the pointer appear How to deal with reverse bias? What should be paid attention to when recording data? If DC digital milliammeter is used for measurement, there will be some problems What is the display? 3. In the experiment of superposition principle, how to make U1 and U2 act separately? Can the non acting one be directly controlled The power supply (U1 or U2) is short circuited to zero?
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- 5. Sinusoidal AC voltage U = 220 root 2Sin (1000t + π / 3) V, which is applied to both ends of a 10 ohm resistor, and the expression of the instantaneous value of the current passing through the resistor What steps should be taken
- 6. The angular frequency of sinusoidal alternating current is the frequency of alternating current?
- 7. Given a vector = (3,5, - 4) and B vector = (2,1,8), then a · B =? The sine value of the angle between a and B is? | a + 2B? =? What is the unit vector collinear with 2a-b? (I can do it, but I can't work out the answer. Help me to do it, and wait for the answer.)
- 8. Is degree a real number? In trigonometric function, the reason why degree is converted to radian is that radian is a real number. That means that degree is not a real number. What is degree, a quantity with unit, is it a real number?
- 9. When the phasor method is used to calculate the sinusoid, Including when calculating impedance, why is 1 / J = - J? What is j? How to calculate the addition and subtraction of phasor? For example, 10 ∠ 0 ° + 5 ∠ - 30 ° + 5 ∠ 90 °
- 10. If two sinusoidal quantities are known as I1 = 10sin (314T + 90 degrees) a and I2 = 10sin (628t + 30 degrees) a, then I1 is 60 degrees ahead of I2, I1 is 60 degrees behind I2, I1 is 90 degrees ahead of I2, or can't switch off the four pairs above If two sinusoidal quantities are known as I1 = 10sin (314T + 90 degrees) a and I2 = 10sin (628t + 30 degrees) a, then A I1 is 60 degrees ahead of I2, B I1 is 60 degrees behind I2, C I1 is 90 degrees ahead of I2, D or can not break the phase difference Which of the four above is right
- 11. Kirchhoff's law and Ohm's law can be applied to any circuit, right? If something is wrong!
- 12. Kirchhoff's law only applies to true current circuits, but not to AC circuits, right?
- 13. Whether the superposition principle is suitable for nonlinear circuits, and explain the reasons
- 14. In a linear circuit, does the voltage and power of each element satisfy the superposition theorem
- 15. Why can't circuit superposition theorem be applied to nonlinear circuits?
- 16. When the sinusoidal alternating current passes through a resistance of 200 ohm, the Joule heat generated in 10 cycles is 4000j What are the effective value and frequency of the alternating current
- 17. In physics, in the chapter of Ampere's loop theorem, H = B / u formula, what does h mean and what is the relationship between H and B
- 18. What is the content of Ampere's loop theorem?
- 19. Under the action of electromagnetic field, human body will be injured in different degrees due to voltage () right or wrong
- 20. Under the action of radio frequency electromagnetic field, biological body absorbs certain radiation energy and produces biological effect