Question

In the circuit shown V tot= 8V. Determine

Answer 1

Usually to determine something in circuits all you need to do is to apply Ohm's law. However sometimes to use this law you might have to simplify the circuit using rules and/or theorems.

Consider the following example: determine current in the circuit.

Solution

We see resistor R connected in series with two resistors R as well connected in parallel. All resistances are 10 Ohms.

Step 1. Simplify

The equivalent resistance will be

$$R_0=R+R/2=3R/2=3\cdot10/2=15\space\Omega.$$

Step 2. Apply Ohm's law:

$$I=V/R_0=8/15=0.53\text{ A}.$$