Three capacitors are arranged as in Fig. 4.1. Find the total capacitance, in $\mu\text{F}$, of the three-capacitor network.
A capacitor with capacitance $45\,\mu\text{F}$ is attached to a variable power supply that is first set to $8.0\,\text{V}$. The supply output is then increased so that the potential difference (p.d.) across the capacitor rises to $9.6\,\text{V}$.\n\nCalculate the increase in stored energy $\Delta E$ in the capacitor.
A sinusoidal a.c. power supply is connected to the input of a bridge rectifier. The rectifier output is connected to a load resistor.\n\nComplete Fig. 4.2 by adding a capacitor to smooth the p.d. across the load resistor.
The change with time $t$ of the p.d. $V$ of the smoothed output is shown in Fig. 4.3. Find the time constant, in ms, of the smoothing circuit.
A sinusoidal a.c. power supply has a maximum power of $16\,\text{W}$. State the mean power when the supply output is full-wave rectified.
A sinusoidal a.c. power supply has a maximum power of $16\,\text{W}$. State the mean power when the supply output is half-wave rectified.