Hi everyone,
I have the following set up:
5V
----------------------------------------------------|---------------------------------------- | | | | Motor Pressure sensor | | 0V 1.5m | |
---------------------------------------------------------------------------------------------|
The electric motor and a pressure sensor are running of the same 5V power supply. The transducer is connected to the power supply with
1.5m long 1 mm diameter cable with resistance of 0.02 ohms/meter.
The motor draws a current of approximately 2 amps when operating.
Now, what I have to do is calculate the drop in supply voltage across the pressure sensor when the motor is turned on.
Now, what I reasoned is that there will be a drop in both the wires:
So, the resistance in the wires are: 1.5 X 0.02 = 0.03 ohms
So the voltage drop when the motor is turned on would be:
2 X 0.03 = 0.06 V
However, it should be 0.06 X 2 = 1.2 V because there are two wires.
Is this reasoning correct? Or is there a special way to add them?
Cheers, Luca