Why voltmeter are connected parallel while ammeter are connected in series .

Dear student,

Voltmeter is device used to find potential difference across ends of a resistor. If that is connected in series it will only be measuring potential difference acrorss itself. The resistor woudl be lying later in the circuit. So the ends of voltmeter are connected to ends of the resistor(parallel) across which we want to measure potential difference.

Ammeter is device used to measure current passing through it. If that was connected in parallel, it would be measuring current just passing though it. But in series, current is same across ammeter and resistor. Hence it measures that.

Regards.