A circuit is designed with a power supply, an ammeter, a sliding rheostat, a switch and several wires Using a power supply, an ammeter, a 0-20 ohm sliding rheostat, a switch and several wires, a circuit is designed to measure the value of unknown resistance Rx. Draw the circuit diagram and write out the expression of Rx value (explain the physical quantity in the formula)

A circuit is designed with a power supply, an ammeter, a sliding rheostat, a switch and several wires Using a power supply, an ammeter, a 0-20 ohm sliding rheostat, a switch and several wires, a circuit is designed to measure the value of unknown resistance Rx. Draw the circuit diagram and write out the expression of Rx value (explain the physical quantity in the formula)

The circuit is as shown in the figure, just take off the voltmeter. ① slide the rheostat R & # 39; to the leftmost end, then the resistance of R 'is 0, and the recorded current is I1. ② slide the rheostat R & # 39; to the rightmost end, then the resistance of R' is 20 Ω, and the recorded current is i2u = i1rxu = I2 (Rx + 20 Ω) i1rx = I2 (Rx + 20 Ω) RX = 20i2 / (I

How to refit a 24 V DC generator to charge a 12 V battery

That's not right! If two batteries are connected in series, the charging voltage should be about 30 v. of course, 24 V is a battery that can't charge 24 V!
You can connect 10 diodes in series at the positive end of the DC generator output, each diode step-down 0.9 V, the voltage will become 15 v. it can be charged! (give you a diode model in5408) try it!
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How to connect two 12 volt batteries in series to form a 24 volt line at the same time
My car has two 12 volt batteries connected in series to form a 24 volt battery. I have a 12 volt screen. If I connect the positive and negative stages of one of the batteries, is it 12 volt? Will this affect the battery,

I don't know what the car is. Suppose it's an electric bicycle. The current intensity of the 24 V power supply should be much higher than that of the 12 V screen power supply. Therefore, it should have little influence to supply power to the screen from one of the two batteries. But we should pay attention to 1. Never connect the short circuit. 2. Confirm the positive and negative poles of the screen power supply. 3. If possible, it's better to exchange the two batteries regularly, so that the screen can use the two batteries in turn

48 V battery is converted to 220 V voltage! Drive two electrical workers? Can it work?
Four batteries, a total of 48 V, a total capacity of 88 A! If you want to use a 100 incandescent lamp and 650 w electric stirrer, can you work together? If you can work for how long?

Your calculation is wrong! A battery of 12V, 22a, you are connected in series, 48V is right, but the capacity is 22a, not 88a. Even if each battery is 88a, then 48V × 88a = 4424 watt hours. If you use inverter, even if the efficiency is 70%, then 3097 watt hours are left