Answer / alok

we know that ammeter has ideally zero resistance so if we connect it in parallel with the ckt then it will short ckt the device in which we are measuring the current.
and we know that voltmeter has large resistance so if we connect it in series then it will open the ckt and will prevent the flow of current.

Answer / hussain

The reason is because current is a measurement of flow - how many electrons are passing through the wire, whereas voltage is a measure of the difference is energies between two points.

In order to measure the amount of electrons passing through a wire, you actually have to place the multimeter within the flow. To measure flow, the multimeter places a VERY LOW resistance into the circuit and measures the voltage drop across that resistance. By using a very low resistance, the multimeter has a negligible impact on the circuit when placed in series.

In order to measure the energies between two points, the multimeter is place in parallel in the circuit with a HUGE resistance and measures the current through the resistance. By using a huge resistance, the multimeter has a negligible impact on the circuit when placed in parallel.

Note: when placing a multimeter into a circuit in series with it turned to the voltage setting or in parallel with the current setting, you will either destroy the multimeter or trigger the circuit breaker or fuse

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