Draw voltage and current waveform in a pure resistro connected to ac

What is the phase relation between voltage and current in a resistor connected to an ac voltage?

What is a phasor diagram ? Draw a phasor diagram when a pure resistor is conneted acorss an a.c. supply and show that current and voltage are in the same phase.

Show diagrammatically the difference between phase behaviours of voltage E and current I in a pure inductive and a pure capacitative a.c. circuit.

A device X is connected across an ac source of voltage V=V_0sinomegat . The current through X is given as I=I_0sin(omegat+pi/2) . Draw graphs showing variations of voltage and current with time over one cycle of ac, for X.