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 300 milliamps of current. If I cut the wire in half and pass 800 volts through it, how many milliamps of current will I measure?
We place 50 volts across this wire and measure 300 milliamps of current THROUGH the wire
(Voltage does not go THROUGH a wire....current does)
V = IR 50 = .3 (R) R = 166 2/3 ohms (300 mAmps = . 3 Amps )
Cut wire in half R2 becomes 1/2 original : 1/2 (166 2/3) = 83 1/3 ohms
WIth 800 V applied:
V = IR
800 = I * 83 1/3 I = 800/(83 1/3 ) = 9.6 amps which is 9600 mAmps
