Write down a general expression for the sinusoidal variation with time t of an alternating current I (you may assume that I and V are in phase).

Write down a general expression for the sinusoidal variation with time t of the power P dissipated due to this current and voltage.

The alternating current I in ampere (A) in a circuit is represented by the equation $I=2.0\sin \left(50\mathrm{\pi t}\right)$. State the peak value of the current.

The alternating current I in ampere (A) in a circuit is represented by the equation $I=2.0\sin \left(50\mathrm{\pi t}\right)$. Calculate the frequency of the alternating current.

The alternating current I in ampere (A) in a circuit is represented by the equation $I=2.0\sin \left(50\mathrm{\pi t}\right)$. Sketch a graph to show two cycles of the variation of current with time. Mark the axes with suitable values.

The alternating current I in ampere (A) in a circuit is represented by the equation $I=2.0\sin \left(50\mathrm{\pi t}\right)$, then calculate $I_{r.m.s.}$ the r.m.s. value of current, and mark this on your graph in part c.

The alternating current I in ampere (A) in a circuit is represented by the equation $I=2.0\sin \left(50\mathrm{\pi t}\right)$. Determine two values of time $t$ at which the current $I=I_{r.m.s.}$.

A heater of resistance 6.0 n is connected to an alternating current supply. The output voltage from the supply is 20V r.m.s. Calculate the average power dissipated in the heater.

A heater of resistance 6.0 n is connected to an alternating current supply. The output voltage from the supply is 20V r.m.s. Calculate the maximum power dissipated in the heater.