To locate null point deflection battery key `(K_1)` ios pressed before the galvanometer `(K_2)` Explanation why?

Explanation

To locate the null point deflection in a potentiometer experiment, it is essential to understand the sequence of pressing the keys (K1 and K2) in the circuit. Here is the step-by-step explanation:

### Step 1: Understanding the Circuit Configuration
In the experiment, we have a battery connected to a potentiometer wire, a key K1 (which connects the battery), a galvanometer with key K2, and a jockey used to find the null point.

### Step 2: Pressing Key K1
First, we press key K1. This connects the battery to the potentiometer wire, allowing a stable current to flow through the wire. It is crucial to establish a steady current in the potentiometer wire before making any measurements.

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