The maximum values of the alternating voltage and current are 400 V and 20 A respectively in a circuit connected to a 50 Hz supply, and these quantities are sinusoidal. The instantaneous values of the voltage and current are 283 V and 10 A respectively at t = 0, both increasing positively. (i) Write down the expression for voltage and current at time t. A - v(t) = 283 sin(2π50t), i(t) = 10 sin(2π50t) B - v(t) = 283 cos(2π50t), i(t) = 10 cos(2π50t) C - v(t) = 283 sin(2π50t), i(t) = 10 cos(2π50t) D - v(t) = 283 cos(2π50t), i(t) = 10 sin(2π50t)