In physics, Ohm's law says that current through a wire, \(I\), is directly proportional to voltage, \(V\), and inversely proportional to resistance, \(R\)
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 300 volts through it, how many milliamps of current will I measure?
I = V/ R
This question has been asked several times before....
Voltage is applied 'across' the wire (not through it) and a current of .2 amps passes 'through' it
.2 = 50 / R Solve for R = 250 ohms
Now cut the wire in half.....this will cut the resistance in half to 125 ohms
and increase the Voltage to 300
Now the current becomes I = V/R = 300 / 125 = 2.4 amps (2400 mAmps)
Edited.... THANX for finding my error , Alan !