In the bridge circuit shown, the capacitors are loss free. At balance, the value of capacitance C₁ in microfarad is ________.

An $$LPF$$ wattmeter of power factor $$0.2$$ is having three voltage settings $$300V,$$ $$150V$$ and $$75V,$$ and two current settings $$5 A$$ and $$10A.$$ The full scale reading is $$150.$$ If the wattmeter is used with $$150V$$ voltage setting and $$10A$$ current setting, the multiplying factor of the wattmeter is __________.

The two signals $$S1$$ and $$S2,$$ shown in figure, are applied to $$Y$$ and $$X$$ deflection plates of an oscilloscope.

The waveform displayed on the screen is

The no-load speed of a 230 V separately excited dc motor is 1400 rpm. The armature resistance drop and the brush drop are neglected. The field current is kept constant at rated value. The torque of the motor in Nm for an armature current of 8 A is ____________.