Question

For the circuit shown in the figure, find the current through and the potential difference across each resistor.

Part A Find the current through 3 Ω resistor.

Part B Find the potential difference across 3 Ω resistor.

 

Answer 1

Solving:

As you can see the 4, 48 and 16 ohms resistors are all parallel and the 3 ohms resistor continues in serial with them.

So you need to find an equivalent value resistor for this group of three resistors, then: 1/R =1/4+1/48+1/16; 1/R=1/3 so R=3 ohms

Now you have two serial resistors with 3 ohms each one, and the uniq resistance is 6 ohms.

Now using the formula I=V/R you can fin the total current: I=12/6=2 A

Answer:

A) Current in 3 ohms resistor is 2 A (because it is in serial position with the others or with the three equivalent resistance)

B) Using the formula V=I*R you can calculate the potencial difference in this resistor. So: V=2*3=6 v