**1.2.** State one way in which a capacitor is similar to a battery.

produces electrical energy

**1.3.** State one way in which a capacitor is different from a battery.

does not use a chemical process

**2.** The area of each plate of a capacitor is 0,05m^{2}. The air gap between the plates is 4mm.

**2.1.** What is the permittivity of free space?

8,85 x 10^{-12}F.m^{-1}

**2.2.** Calculate the capacitance of this capacitor.

**2.3.** This capacitor is now connected to a 200V DC source.

**2.3.1.** Calculate the charge that accumulates on each plate.

**2.3.2.** Which parts of a capacitor are considered “physical designs?”

A (area of plates) and d (distance between plates)

**2.3.3.** How can the amount of charge stored on each plate be increased without altering the physical design of the capacitor.

increase voltage of battery

**2.4.** Assume that the capacitor is now fully charged. The battery is removed and replaced with a bulb.

**2.4.1.** Will the bulb remain glowing for an extended period of time? Explain.

No. Capacitor will quickly discharge.

**2.4.2.** In which direction will the current flow compared to the current direction when the battery was operational.

opposite

**3.** The charge on one capacitor plate is 8 x 10^{-10}C and the voltage across the plates is 200V.

**3.1.** What is the charge on the other plate?

-8 x 10^{-10}C

**3.2.** What s the net charge of the plates?

zero

**3.3.** Calculate the capacitance of the capacitor.

**3.4.** If the area of a plate is 50cm^{2}, calculate the distance between the plates.

**4.** To maximise the capacitance of a capacitor, state whether each of the following must be maximised or minimised.

**4.1.** area of the plates

maximised

**4.2.** dielectric permittivity

maximised

**4.3.** separation distance of plates

minimised

**5.** Study the following graphs

**5.1.** Which graph shows capacitance against plate area?

Graph A

**5.2.** Which graph shows capacitance against plate separation?

Graph D