Electronic Formulas Page
Ohms Law
Ohm’s law states that the voltage across a conductor is directly proportional to the current flowing through it, provided all physical conditions and temperatures remain constant.
To demonstrate this a demo circuit was set up.
The circuit is put together and given the values the expected result is
1.5v ÷ 10.09Ω = 0.148A or 148mA
A you can see the answer was not as expected but instead 104.43mA. The reason for this is that the circuit has additional resistance due to the multi-meters.
Luckily we are measuring these values
Looking a first measurement over the resistor
R1 = V/I
= 1.05v ÷ 0.104A = 10.09ΩLooking a second measurement over the multi-meter
RA = V/I
= 0.21v ÷ 0.104A = 2.02Ω