Charles law Essay Example for Free

Charles law EssayAim To investigate how the prosecute on a capacitance is related to the p. d. applied across it by charging the condenser at a never-ending rate. Apparatus o Capacitor (electrolytic type) 500 ? F o Microammeter 100 ? A o tog component holder o Stop-watch o CRO o Connecting leads Theory From definition, the capacitor C of a capacitor is found from C = Q/V Where Q is the charge stored on the capacitor and V is the potential contrariety across it. == Q = CV ==. If a capacitor is charged up at a constant rate, i. e., where I is a constant. Then is also constant. Hence the potential difference across the capacitor increases linearly with clock. cognitive process 1. The circuit was connected as shown in the figure below. The CRO was set to d. c. and the sensitivity to 1 V/cm. 2. The time base was set to any high value so that a steady plane vestige is displayed. The trace was shifted to the bottom of the screen. 3. The capacitor was shorted reveal by connect ing a lead across it and even off the 100 k ? potentiometer for a suitable current, say 80 ?A. 4. Shorting lead was removed and the capacitor will charge up. Note what happens to the microammeter reading and the CRO trace. 5. The procedure was repeated but this time detonate the stop-watch and incessantly adjust the potentiometer to keep the current constant as the capacitor charges up. 6. The times was deliberate for the CRO trace to move up by 1 cm, 2 cm, 3 cm, etc. These are the times for the p. d. across the capacitor to reach 1V, 2V, 3V, etc. 7. The results was tabulated. Results and discussion.8 Describe what happens to the microammeter reading and the CRO trace as the capacitor is being charged up. The microammeter reading increase momentarily, then it decrease to zero in a few second. After the capacitor had been completely charged,the CRO trace is a horizontal line, which continuously move up. 9 Tabulate the times for the p. d. across the capacitor to reach 1 V, 2 V, 3 V, etc. as below P. d. across capacitor Plot a graph of p. d. across the capacitor against time.How is the p. d. related to the time? p. d. is directly proportional to time. 11 Deduce a relationship between the charge on the capacitor and the p. d. across it. From the graph it is found that p. d. is directly proportional to time. Since Q=CV = V=Q/C Therefore if V across the capacitor is directly proportional to t, Q is directly proportional to time as current was constant. Conclusion We can find out that the p. d. across the capacitor is directly proportional to the time needed. Given that the charging current is constant. Sharing.The experiment is much easier than the last one , but we encountered some obstacles in connecting wires , as usual , we messed up positive and negative terminals and couldnt conduct it smoothly. At last, we had to call for help. Suggestion and there whitethorn be some personal error , for example counting the time taken for the capacitor be charged to ext ent value was rather inaccurate. Perhaps, we could conduct the experiment several times and compute out the average value.Reference list http//en. wikipedia. org/wiki/Capacitor http//www. elecsound. cn/Ceramic-Capacitor. htm.