How will you conclude that the same potential difference [voltage] exists across three resistors connected in a parallel arrangement to a battery?

Explanation

The experimental setup comprises three resistors `R_(1),R_(2)andR_(3)` which are joined in parallel combination and connected with a battery, an ammeter [A], a voltmeter [V] and a plug key K, as shown in Fig. [a]. The key K is closed, and the voltmeter and ammeter readings are recorded.

The key K is open and removing the ammeter and voltmeter form the circuit and insert the voltmeter V in parallel with `R_(1)`, and ammeter in series with the resistor `R_(1)`, as shown in Fig. [b].
Again, the voltmeter and ammeter readings are recorded.
Similarly, measuring the potential differences across resistances, `R_(2)andR_(3)`, it is found that voltmeter gives identical reading which leads to conclude that the voltage or potential difference across each resistor is same and equal to the potential difference across the combination.