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Is ohms law obeyed in a circuit with a cell and a resistor?

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Chris Bachegalup Preliminary Investigation Science coursework Is ohms law obeyed in a circuit with a cell and a resistor? Knowledge and Understanding Ohms law is a group of formulas used to calculate Voltage (V), Current (I) and Resistance (R) in a circuit. It is used to calculate a missing value in a circuit. It was named after the German physicist Georg Simon Ohm, who was born in 1787 and died in 1854. The voltage is measured in volts, the current is measured in amperes and the resistance is measured in ohms. An easy way to remember the formulas is by using the following diagram: To find a missing value, cover it with your finger. The horizontal line in the middle means to divide the two remaining values. The "X" in the bottom section of the circle means to multiply the remaining values. ...read more.


weaker current - For example - A curved line graph. Metals conduct electricity in their solid state or when they are melted but they are not decomposed in the process. (I.e. - a chemical reaction does not occur) Metals can conduct electricity because in their structure, each metal atom gives up its outer shell electrons to form a sea of unlinked electrons. This means that the electrons are free to move through the metal's structure and therefore conduct electricity. Prediction I predict that the results, which will appear on my graph, will be straight. This will show that ohms law has been obeyed. Apparatus Power pack Voltmeter Ammeter Resistor Wires Crocodile Clips Plan The following experiment took place to see if ohms law was obeyed First we set up the equipment as follows: For the experiment we would turn the power pack on and touch the metal part of the resistor with the crocodile clips, which were attached to the voltmeter. ...read more.


Current Ohms (?) 1.30 0.27 5 2.23 0.50 5 3.60 0.81 5 4.60 1.05 5 6.00 1.35 5 7.01 1.58 5 8.40 1.89 5 9.40 2.12 5 10.40 2.36 5 3rd set Voltage (volts) Current Ohms (?) 1.30 0.27 5 2.60 0.50 5 3.60 0.81 5 4.60 1.04 5 6.00 1.35 5 7.00 1.59 5 8.20 1.90 5 9.40 2.12 5 10.40 2.35 5 Average Voltage (volts) Current Ohms (?) 1.28 0.27 5 2.25 0.50 5 3.60 0.81 5 4.60 1.04 5 6.00 1.35 5 7.00 1.58 5 8.33 1.89 5 9.40 2.12 5 10.40 2.36 5 Analysis Looking at my results from the graphs (plotted from the results from the tables, shows that my results are correct and that ohms law has been obeyed. I know this because the gradient is a straight line that shows a pattern on the graph (the straight line). ...read more.

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