Consider the following electric circuit:
The current in the above electric circuit is:
CONCEPT:
There are mainly two ways of combining resistances:
1. Resistances in series combination
2. Resistances in parallel combination
- When two or more resistances are connected one after another such that the same current flows through them- this system is called series combination
The net resistance/equivalent resistance (R) of resistances in series is given by:
Equivalent resistance, R = R1 + R2
- When the terminals of two or more resistances are connected at the same two points and the potential difference across them is equal is called as resistances in parallel.
The net resistance/equivalent resistance(R) of resistances in parallel is given by:
\(\frac{1}{R} = \frac{1}{{{R_1}}} + \frac{1}{{{R_2}}}\)
Calculation:
The 10Ω and 0Ω resistors are in parallel:
⇒ 1/Rparallel = 1/10 + 1/0
⇒ Since 1/0 is undefined, the parallel combination results in 0Ω for practical purposes.
⇒ The total resistance in the circuit is the sum of the series of resistances:
⇒ Rtotal = 5Ω + 0Ω + 5Ω
⇒ Rtotal = 10Ω
⇒ Using Ohm's Law to find the current:
⇒ I = V / Rtotal
⇒ I = 10V / 10Ω
⇒ I = 1A
∴ The current in the given electric circuit is 1A.
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