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Ohm's law in closed circuit U = E / R / R + I (to explain, u is the road voltage, e is the power electromotive force, e is the numerator, R / R + I is the denominator, R / R + I means the quotient of R divided by R plus I). How did this formula come out? Thank you!
E / u = (R + R) / R, derived from this, because in the circuit, the voltage ratio of each part is equal to the resistance ratio, the electromotive force of the power supply is the total voltage of the circuit, and the terminal voltage is the total voltage of all parts except the power supply, so the terminal voltage on the electromotive force ratio is equal to the total resistance of the circuit except the power supply. The previous formula can be changed to u = E / [(R + R) / R], and then u = E / [(R / R) + 1]
Ohm's law of closed circuit and its application
Please describe it in detail and summarize the formula
Ohm's law of knowledge summary (eight years of Physics) core tips: first, to explore the relationship between the current root on the resistance and the voltage at both ends. Experimental research methods: control variable method. When the resistance is fixed, the current in the conductor is directly proportional to the voltage at both ends of the conductor. When the voltage is fixed, the current in the conductor is inversely proportional to the resistance of the conductor
RELATED INFORMATIONS
- 1. Ohm's law of closed circuit Is the terminal voltage necessarily the power supply voltage? What are the internal resistance and external resistance? What are their differences and connections?
- 2. Calculation of maximum power of sliding rheostat by Ohm's law of closed loop If the sliding rheostat is connected in parallel with a resistor, how can the resistor be equivalent to the internal resistance
- 3. Nowadays, there are many devices using batteries as power supply, and the amount of batteries used is very large. Some of them are rechargeable batteries, such as battery car batteries and automobile batteries. These rechargeable batteries all have one feature: the newly purchased batteries can be used for a long time after charging. After long-term use, they will be fully charged, and the power will soon run out. Please use Ohm's law of the whole circuit for analysis! Thank you for your explanation!
- 4. The trajectory of a point whose distance from the plane to the fixed point O is equal to 2cm is ()
- 5. There are two fixed points a and B in the plane, and | ab | = 2. The ratio of the distance between a moving point m and two points a and B in the plane is 2:1
- 6. Two fixed points a (- C, 0), B (C, 0). The sum of the distances from the moving point P to the two fixed points is a constant 2A. Find the trajectory equation of point P
- 7. Given that the distance from the moving point P to the fixed point F (3,0) and to the fixed value line x = 5 / 2 is constant 2 √ 3 / 3, the trajectory equation of point P is obtained Urgent``
- 8. In the space rectangular coordinate system, the point a (1,0,2) B (1, - 3, - 1) m is on the Y axis, and the distance to a and B is equal In the space rectangular coordinate system, if the point a (1,0,2) B (1, - 3, - 1) m is on the Y axis and the distances to a and B are equal, then the coordinate of M is?
- 9. In Cartesian coordinates, the distance OP from point P (- 2,3) to the origin=______ ．
- 10. In Cartesian coordinates, the distance from the point P (- 1, (√ 3) / 2) to the origin o is
- 11. As shown in the figure, line a is the U-I diagram line of a power supply, and line B is the U-I diagram line of resistance R. when the power supply and the resistance are used to form a closed circuit, the output power and internal resistance of the power supply are () A. 4W，1ΩB. 6W，1ΩC. 4W，0.5ΩD. 2W，0.5Ω
- 12. The variation law of the terminal voltage U of a power supply with the resistance R of the external circuit is shown in figure (a), and the straight line of u = 12V in the figure is the asymptote of the line. Now, the power supply and a rheostat R0 are connected into the circuit as shown in Figure (b). It is known that the maximum allowable current of the power supply is 2a, and the maximum resistance of the rheostat R0 = 22 Ω (1) The results are as follows: (1) the electromotive force E and internal resistance R; (2) the output voltage range of a and B at no load; (3) the minimum resistance of a and B that can be connected to load
- 13. Ohm's law There are 6V 3W and 3V 1W bulbs, which are connected in series in a 9V circuit. In this paper, which bulb is connected with a resistor in parallel can make both lamps light normally. Why?
- 14. 1. The voltage at both ends of the circuit is 6 V, the resistance of R1 is 8 Ω, and the current through L1 is 0.2A Solution: 1. Current through L2. 2. Voltage at both ends of L1. 3. Voltage at both ends of L2. 4. Resistance of L2 2. R1 and R2 are connected in series in a circuit with a voltage of 6 v. the current passing through the resistor R1 is 0.2 a, R2 = 10 Ω, and the resistance of R1 is calculated The first question is series connection
- 15. To measure the resistance of a resistance, according to the deformation formula of Ohm's Law (), just use () to measure To measure the resistance value of a resistance, according to the deformation formula of Ohm's Law (), as long as you use () to measure the voltage at both ends of the resistance () and () to measure the current through the resistance, you can calculate the resistance value. This method of measuring resistance is called ()
- 16. Use resistance, sliding rheostat, power supply and ammeter to measure rated power of bulb The resistance is known
- 17. When using volt ampere method to measure resistance, it is found that the voltmeter and ammeter have small indication after closing the switch. What is the reason that the bulb is not on To see clearly, the ammeter and voltmeter have small indication and the bulb is not bright. The original title is written like this
- 18. I want to ask a question: if in the experiment, the corresponding current value and voltage value have been given, the resistance value can be obtained by Ohm's law If the results are very different each time, what may be the reason? For example, why are the results different when using a fixed circuit diagram to measure the resistance of the same small lamp? The reason why the resistance value changes is that it is always on for measurement. Does the resistance have a certain temperature? Thank you for your reply
- 19. When the resistance is constant, the greater the voltage, the greater the current (). When the voltage is constant, the smaller the resistance, the greater the current ()
- 20. It is proved by Ohm's law and the law of current and voltage in series circuit that R is always equal to R1 plus R2 Urgent need