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 50 volts through this wire and measure 200 milliamps of current. If I cut the wire in half and pass 250 volts through it, how many milliamps of current will I measure?

 Feb 9, 2020

First of all ...you do not  'pass 50 volts through a wire'    you apply 50v across a wire and pass a current through the wire.....


I = V/R    

.2  = 50/R         R of the wire is  250 ohms

    1/2 of the wire would be    125 ohms



Now apply 250 v   across the wire


I = V/R

I = 250/125   =   2 amps  (2000 miliamps)

 Feb 9, 2020

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