Resistance Physics Example 3

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Example 3

easy
If the resistance of a wire doubles and the voltage stays the same, what happens to the current?

Solution

  1. 1
    From Ohm's law: I=VRI = \frac{V}{R}.
  2. 2
    If RR doubles: I′=V2R=12⋅VR=I2I' = \frac{V}{2R} = \frac{1}{2} \cdot \frac{V}{R} = \frac{I}{2}

Answer

The current is halved.\text{The current is halved.}
Current is inversely proportional to resistance at constant voltage. Doubling resistance halves the current.

About Resistance

A measure of how strongly a material opposes electric current, measured in ohms (Ω\Omega) — higher resistance means less current for a given voltage.

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A resistor carries [formula] of current when [formula] is applied across it. What is the resistance?

Example 2 medium

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Example 4 medium

A wire has resistance [formula]. If you replace a wire with one that is twice as long and has three

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