What is the total resistance in the following circuit element?
3R/2
The correct answer is option "4"
Concept :
Resistance:
- The measurement of the opposition of the flow of electric current through a conductor is called resistance of that conductor. It is denoted by R.
There are mainly two ways of the combination of resistances:
1. Resistances in series:
- When two or more resistances are connected one after another such that the same current flows through them are called as resistances in series.
- The net resistance/equivalent resistance (R) of resistances in series is given by:
- Equivalent resistance, R = R1 + R2
2. Resistances in parallel:
- 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 resistances in parallel.
- The net resistance/equivalent resistance(R) of resistances in parallel is given by:
\(\frac{1}{{{R_{eff}}}} = \frac{1}{{{R_1}}} + \frac{1}{{{R_2}}}\)
Series Combination | Parallel Combination |
In series, voltage is divided through each of the connected resistors. | In parallel, the current is divided through each connected resistor. |
In series, the Current will be the same throughout the circuit. | In parallel, the Voltage will be the same throughout the circuit. |
Calculation:
In the given figure of resistance two identical resistances "R" are in parallel and then in series with otherr identical resistance "R"
The parallel combination of R and R would be
R' = R×R/(R + R)
R' = R/2
The R' is in a series with R.
So R equivalent would be
Req = R/2 + R
= 3R/2
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