How to find node voltage by VDR

Question

how to determine the node voltage Vab using VDR.

Circuit diagram

Answer 1

You should ask questions like this on the electrical engineering Stack Exchange site here: https://electronics.stackexchange.com/

But anyway, since the resistors are all in series you can use the simple series resistance formula to find that the total series resistance is:

Rt = 2.5 + 1.5 + 0.6 + 0.9 + 0.5 = 6 Ohms

This means the current through the circuit is:

I = V/R = 0.36/6 = 0.06 A (60 mA)

The voltage across Vab is Vab = Va - Vb so:

Va = IR = 0.06 * 0.5 = 0.03 V (30 mV)
Vb = IR = 0.06 * (1.5 + 0.6 + 0.9 + 0.5) = 0.06 * 3.5 = 0.21 V (210 mV)
Vab = 0.21 - 0.03 = 0.18 V (180 mV)

This can be shortened to:

Vab = IR = 0.06 * (1.5 + 0.6 + 0.9) = 0.18 (180 mV)

To further your learning I would suggest learning about Ohm's law