The reciprocal of resistance is called

Options

A. conductance
B. friction
C. specific resistance
D. reaction

Explanation

To solve the question, "The reciprocal of resistance is called," we can follow these steps:

### Step 1: Understand the Concept of Resistance
Resistance is a measure of the opposition to the flow of electric current in a circuit. It is denoted by the symbol \( R \) and is measured in ohms (Ω).

### Step 2: Define the Reciprocal of Resistance
The reciprocal of resistance is mathematically expressed as \( \frac{1}{R} \). This means that if you take the value of resistance and find its reciprocal, you will get a new quantity.

### Step 3: Identify the Term for the Reciprocal of Resistance
The term that refers to the reciprocal of resistance is called **conductance**. It is denoted by the symbol \( G \).

### Step 4: State the Relationship
The relationship can be summarized as:
\[ G = \frac{1}{R} \]
where \( G \) is conductance and \( R \) is resistance.

### Step 5: Determine the Unit of Conductance
The unit of resistance is ohms (Ω). Therefore, the unit of conductance, being the reciprocal of resistance, is:
\[ \text{Unit of Conductance} = \frac{1}{\text{Ohm}} = \text{Ohm}^{-1} \]
This is often referred to as siemens (S).

### Final Answer
The reciprocal of resistance is called **conductance**.

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