+84 In physics, Ohm's law says that current through a wire, $I$, is directly proportional to voltage, $V$, and inversely proportional to resistance, $R$:
I = V/R
It's also true that resistance is directly proportional to the length of the wire. We have a piece of wire. We pass $500$ volts through this wire and measure $25$ milliamps of current. If I cut the wire in half and pass $175$ volts through it, how many milliamps of current will I measure?
+3311
We have a piece of wire. We pass $500$ volts through this wire and measure $25$ milliamps of current.
If I cut the wire in half and pass $175$ volts through it, how many milliamps of current will I measure?
V = I • R ==>> R = V / I ==>> R = 500 Volt / 25 mA
R = 500 Volt / 0.025 Amp
R = 20,000 Ω
V = I • R ==>> I = V / R ==>> I = 175 Volt / 10,000 Ω
I = 0.0175 Amp
I = 17.5 mA
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