Why does a voltmeter display A reeded of 0 V when both of these probes are toasted the same in a battery?

A voltmeter displays 0 V when both probes are connected to the same terminal of a battery because there is no potential difference between the two points. Since both probes are at the same voltage level, the voltmeter reads zero, indicating that there is no voltage to measure. Essentially, it measures the difference in electric potential, and with both probes on the same terminal, that difference is zero.