An $AC$ voltmeter in an $L-C-R$ circuit reads 30 volt across resistance, 80 volt across inductance and 40 volt across capacitance. The value of applied voltage will be

কোনো দিক পরিবর্তী তড়িচ্চালক শক্তির গড়বর্গের বর্গমূল মান 10 V । তড়িচ্চালক শক্তির শীর্ষমান হলো— 

The phase difference between alternating emf and current in a purely capacitive circuit will be

The instantaneous voltage through a device of impedence $20\Omega$ is $e=80\sin { 100\pi t }$. The effective value of the current is

A circuit operating at $\dfrac{360}{2\pi }$ Hz $\Omega$ contains a 1 F $\mu$ capacitor and a 20 resistor. The inductor must be added in series to make the phase angle for the circuit zero is