Aim: To observe the direction of the forces between two parallel CCDs. Hypothesis: That the CCD with current flow in the same direction will be attracted to each other and CCDs with current flow in opposite directions will repel. Apparatus: -Variable DC power supply
* Variable resistor (15ohm rheostat)
* Connecting wires
* Retort stand
* Two pieces of thick card or balsa wood 10cmx10cm
* Two strips of aluminium foil 1cmx30cm
* Four drawing pins
* Push switch
Method: 1. Pin each foil strip between the pieces of card so that they are parallel with the top card and is supported by the clamp and retort stand. 2. Connect the wires to the power packs DC terminals, switch variable resistor and strips as shown in diagram. This will produce currents in the strips that are flowing in opposite direction. 3. Set the power pack to its lowest voltage and turn it on.
4. Briefly close the switch and record the movement of the foil strips. 5. Connect the wires to the power packs DC terminals, switch, variable resistor and strips as shown in diagram. This will produce currents in the strips that is flowing in the same direction. 6. Briefly close the switch and record the movement of the foil strips. Bottom Card
Results: When the current was flowing in the same directions through both strips they would be attracted to each other but when the current was flowing in opposite directions they would repel.
Discussion: This occurs due to the magnetic field created by the current. When the current is travelling in the same directions the north and south magnetic fields are closer and cause it to attract but when they are opposite the south and north fields are closest causing it to repel. Analysis: All electric currents cause magnetic fields and using the right hand rule, we can find which way the magnetic field is going by the direction the current is...