1. The Professional Development Service for Teachers is funded by the Department of Education and Skills under the National Development Plan Capacitance T.T.

2. PDST Resources for Leaving Certificate Physics 2 Capacitance The Capacitance of a body is defined as the ratio of the charge (Q) on the body to its potential (V): Q = charge V = potential ++++++ ------ ++++++++++ ---------- A capacitor is device used to store energy. Two metal plates facing each other increases the charge that each can store.

3. PDST Resources for Leaving Certificate Physics 3 ++++++ ------ ++++++++++ ---------- Capacitor capacitance of a capacitor energy stored in a capacitor See demonstration experiments

4. PDST Resources for Leaving Certificate Physics 4 To demonstrate that a capacitor stores energy Method: Set up the apparatus as shown. Allow the capacitor to build up a charge. Disconnect it from the generator Bring a conducting wire from each plate to the bulb Observation:The bulb flashes Conclusion:The presence of light energy indicates that energy had been stored on the capacitor Describe an experiment to demonstrate that a capacitor can store energy. (12) ++++++ ------ ++++++++++ ---------- Van De Graaf bulb capacitor