CAPACITORS

OBJECTIVES

This report aims to:

• Introduction of a capacitor.

• The basic construction of a capacitor.

• Factors that effect its ability to store charge on its plate.

BACKGROUND THEORY

In this experiment will be used a power supply, 100μf capacitor and 100 KΩ resistor.

• Power supplies gives a source of power, rated as maximum voltage and current output

• Capacitor is an element constructed simply of two surfaces separated by the air gap. The capacitor displays its true characteristics only when a change in the voltage or current is made in the network.

EQUIPMENT

·         Power supply                          (GW GPS-3030PP, Serial Number: EG820606)

·         One 100KΩ resistor

·         One 100μF Capacitor

EXPERIMENTAL METHOD AND PROCEDURE

Part 1

The 20V power supply was connected in series with the 100KΩ resistor and the 100μf capacitor. The voltage across the capacitor during charging and discharging in any τ was measured (table 1a, 1b). Then the voltage across the resistor during charging and discharging in any τ was measured (table1a, 1b). τ=RC. The current through the capacitor was calculated (table1a, 1b) using the following equation: iR = Vc / R

OBSERVATIONS

Table 1a capacitor during charging

Table 1b capacitor during discharging

Data discussion

Capacitor is an element constructed simply of two surfaces separated by the air gap. The capacitor displays its true characteristics only when a change in the voltage or current is made in the network.

The basic construction of a capacitor is a component that opens the door to all types of practical application, stretching from touch pads to sophisticated control system.

Two parallel plates of a material such as aluminous had been connected through a switch and a resistor to a battery when the switch is closed,, electrons are drown from the upper through the resistor to the positive terminal of a battery. This action creates a net positive charge on the top plate. Electrons are being repelled by the negative terminal through the lower conductor to the bottom plate at the same rate they are being drown to the positive terminal. Final result is a net positive charge on the top plate and a negative charge on the bottom plate.   

Theoretic the capacitor want 5τ to get fully charge and another 5τ to get fully discharge. On the experiment seeing that the capacitor did not get fully charge or discharge. In 38s the capacitor charged 18,1V instead of 20v and in another 38s the capacitor discharge to 0.5 instead of 0V. 

During the charge phase seeing that by using KVL, the voltage across the capacitor + the voltage across the resistor equal to the source of the power supply. (Table 1a, 1b) Vc=9.6V VR=9.9 at 7.6s. Vs=9.6+9.9=19.5V. However in theoretical the Vs =20V.

During the charge phase seeing that the voltage across the resistor is positive and during the discharging phases the voltage change to negative. This fact aught to that when the battery is closed, the direction of the current changed and goes to the opposite direction. At 7.6s charge the VR= 9.9V and at 7.6 discharge the VR=-8.1V

RECOMMENDATIONS

Capacitor is an element constructed simply of two surfaces separated by the air gap. The capacitor displays its true characteristics only when a change in the voltage or current is made in the network.

The basic construction of a capacitor is a component that opens the door to all types of practical application, stretching from touch pads to sophisticated control system.

Two parallel plates of a material such as aluminous had been connected through a switch and a resistor to a battery when the switch is closed,, electrons are drown from the upper through the resistor to the positive terminal of a battery. This action creates a net positive charge on the top plate. Electrons are being repelled by the negative terminal through the lower conductor to the bottom plate at the same rate they are being drown to the positive terminal. Final result is a net positive charge on the top plate and a negative charge on the bottom plate.