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When a resistance is increased by 3 Ω, the current in the circuit becomes four fifths of the original value. If the supply voltage remains unchanged, what is the original value of the resistance?
twelve
What is the effect of resistance on current and voltage in series circuit?
I don't know the relationship between resistance voltage and current in series and parallel connection. It's very confusing. Give me some knowledge about this, let me straighten it out··
In series circuit, the current of each consumer is equal and the voltage is proportional to the resistance; in parallel circuit, the voltage of each consumer is equal and the current is inversely proportional to the resistance
If the resistance is 8 ohm and a planting resistance R is connected in series, and the voltage is inconvenient, if the resistance is increased to 10 ohm, what is the current variation range?
The resistance range of R is greater than 0 and less than 10 Ω
I0 = u / 8 (maximum current) at r = 0
I1 = u / 8 + 10 (minimum current) when r = 10
Then (i0-i1) / Io * 100% = 55.55555 %
The current change is not greater than 55.5555 of the current before increasing the resistance %
The resistance of a circuit is increased by 4 ohm, and the circuit becomes 2 / 3 of the original. If the voltage of the circuit remains unchanged, the later resistance in the circuit is (steps required)
Then the later resistance in the circuit is 8 + 4 = 12 ohm
RELATED INFORMATIONS
- 1. How to change resistance, current and voltage in series / parallel circuit? The sliding rheostat changes the resistance in the circuit. How do the current and voltage at both ends of the planting resistor change? How do the total voltage and current change?
- 2. How to change resistance current and voltage with sliding rheostat in series circuit? How to change resistance current and voltage with sliding rheostat in parallel circuit
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- 8. The resistance of a conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the current passing through the conductor Why wrong? How to understand the relationship between resistance, voltage and current? Don't use books. It's suitable for multiple choice questions
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- 11. It is known that the circuit has two fixed value resistors, a switch and a 60V power supply connected by wires. And the power supply voltage is constant. When the switch is in a certain state (open or closed), the electric power of the circuit is 40W. When the switch is in another state, the electric power of the circuit is increased by 20W. The resistance values of the two fixed value resistors are calculated
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- 17. In the experiment of exploring the relationship between current and resistance, the slide of sliding rheostat is adjusted to keep the voltage at both ends of the resistance unchanged. If the voltage does not change, does not the current also change? Does not the calculated resistance also change?
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