免费电阻计算器
根据欧姆定律计算电阻值。
V
A
电阻
24.0000 Ω
Resistance vs Voltage
公式
## Resistance Resistance measures how strongly a component opposes the flow of electric current. ### Formula **R = V / I** Derived from Ohm's law. The unit is the ohm (Ω), named after Georg Ohm.
计算示例
A 12 V battery drives 0.5 A through a resistor.
- 01R = V / I
- 02R = 12 / 0.5
- 03R = 24 Ω
常见问题
What factors determine the resistance of a wire?
Resistance depends on the material (resistivity), length, cross-sectional area, and temperature: R = rho * L / A.
Does resistance change with temperature?
Yes. For most metals, resistance increases with temperature. For semiconductors, it typically decreases.
What is a resistor color code?
A system of colored bands on resistors that encode their resistance value. Each color represents a digit or multiplier.
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