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Ohm's law of the whole circuit points out that the current in the circuit is determined by the internal resistance of the power supply and the load resistance A power B voltage C resistance D electromotive force,
Choose D
A power: the power of general power supply refers to the maximum output power. The output power will change with different loads. For example, if a dry battery is connected with one bulb and two bulbs, the output power is different
B. Generally speaking, voltage refers to the terminal voltage of the power supply, that is, the output voltage, which will change with the load
The resistance of C, which generally refers to the internal resistance of the power supply, has been included after the brackets
D and B are similar, but the electromotive force is equal to the total voltage of the power supply, that is, the output voltage B plus the voltage divided by the internal resistance of the power supply
The electromotive force E of the power supply is 2V, which is connected with the resistance of the load with r = 5 Ω to form a closed circuit. The voltage of the two sections of the power supply is measured to be 1.8V, and the internal resistance R of the power supply is calculated
According to KVL, if the voltage drop of internal resistance of power supply is 2-1.8 = 0.2V and the loop current is 1.8/5 Ω = 0.36A, then the internal resistance of power supply is ro = 0.2v/0.36a = 0.56 Ω
If the electromotive force of power supply e = 4.5V, the internal resistance R = 0.5V and the load resistance R = 4 Ω, the current I =? Terminal voltage U =?
I=E/(R+r)=1A
Terminal voltage U = I * r = 4V
RELATED INFORMATIONS
- 1. The electromotive force of the power supply is e, the internal resistance is r, and the power supply supplies power to the variable resistance R. is the following statement about the terminal voltage correct? Why Because u = IR, when R increases, does the terminal voltage also increase
- 2. How much resistance should a 36V, 60W arc lamp be connected in series in order to make it shine normally in the circuit with 110V supply voltage
- 3. A "6V, 0.5A" small bulb connected in series with a 24 ohm resistor is connected to a power supply, which can make the small bulb work normally. What is the power supply voltage? (with the knowledge solution of elementary 2)
- 4. When a small light bulb works normally, the current is 0.5A and the resistance is 5 Ω. Now connect it to the circuit with voltage of 6V to make the small light bulb work normally, Should_____ Connect a resistance value of__________ Ohm resistance
- 5. When an inductive coil is connected to the U = 220 V DC power supply, the current is I = 20 A; when it is connected to the F = 50 Hz, u = 220 V AC power supply, the current is I = 20 a
- 6. An inductive coil is connected to a DC source of u = 120V, I = 20A. If it is connected to an AC source of F = 50 Hz, u = 220 V, I = 28.2a. Calculate the coil resistance and inductance
- 7. How to use DC power supply to realize input AC 220 V and output DC 110 V
- 8. It is known that the complex impedance of each phase of the star connected load is Z = 12 + j16 Ω. When it is connected to a symmetrical three-phase power supply, the line voltage is 380V, and the line current is calculated If the three-phase load is changed to triangle connection, what is the line current?
- 9. If the line voltage of the power supply is 380V and the load impedance is 110 Ω, the line current and phase current of the circuit can be calculated
- 10. The voltage of a certain section of circuit is 120V, and the current flowing is - 2.5A. Do you want to know whether this section of circuit generates power or consumes power? What is the power? I The voltage of a certain section of circuit is 120V, and the current flowing is - 2.5A. Do you want to know whether this section of circuit generates power or consumes power? What is the power? I need it urgently
- 11. The same voltage power supply in parallel, in each power supply in series with a very small resistor can balance the current, what is the principle? Several power supplies of the same voltage are connected in parallel to provide large current. A small resistor in series on each power supply can balance the current. What is the principle? Now I also want to prevent one of the power supplies from breaking down and affecting other power supplies. Therefore, a diode is connected to each power supply, and the diode also has a certain resistance. Can it not only prevent the current from flowing back, but also balance the current? Can diode be connected in series instead of resistor? I know that the purpose is to prevent the current from flowing back, but what is the principle to facilitate my future use,
- 12. The equivalent resistance of the two terminal network is 10 ohm, the open circuit voltage is 40 V, and the maximum power consumed by the load is?
- 13. When the power supply voltage is fixed, the load with large resistance is a large load? Isn't it true that the size of the load is only related to the current? I remember the book said that the load with large current is called large load, so in the series circuit, the current is equal everywhere, and there will be different loads?
- 14. Find the maximum power of load resistor RL in the circuit below
- 15. There is a light bulb marked with 220 V, 100 W (1) The bulb is normally emitting. What is the current passing through the bulb? What is the resistance of the bulb? (2) How much power is consumed when the bulb works normally for 10 minutes?
- 16. The bulb is marked with PZ 220 V 100 W, which is connected to 220 V power supply. What is the actual power
- 17. The consumer with resistance R is connected to the power supply, and the current passing through the consumer is I, so that the current passing through the consumer is reduced to 1 / 3 of the original. A () resistor should be connected to the consumer in series
- 18. 12V / 2A regulated power supply is out of order. It can be replaced by 12V / 1.2A regulated power supply, but will it damage electrical appliances?
- 19. If the voltmeter is connected in parallel with the consumer and power supply, whose voltage is measured by the voltmeter
- 20. The voltmeter should be connected in parallel with the measured appliance,