TEST OF PRACTICAL KNOWLEDGE QUESTION You have been provided with a resistance box, a voltmeter, a key, a battery, and other necessary materials. Connect the...

TEST OF PRACTICAL KNOWLEDGE QUESTION

You have been provided with a resistance box, a voltmeter, a key, a battery, and other necessary materials.

• Connect the circuit as shown in the diagram above.
• With the key K closed, read and record the voltmeter reading V\(_{0}\).
• Set the resistance R in the resistance box equal to I\(\Omega\).
•  Close the key, read and record the potential difference V on the voltmeter.
• EvaluateR\(^{-1}\) and V\(^{-1}\) .
• Repeat the procedure for five other values or R = 2\(\Omega\), 3\(\Omega\), 4\(\Omega\), 5\(\Omega\) and 6\(\Omega\).
• Tabulate your readings.
• Plot a graph with V\(^{-1}\) on the vertical axis and R on the horizontal axis.
• Determine the slope, s, of the graph and the intercept, C, on the vertical axis.
• Evaluate c\(^{-1}\)
• State two precautions taken to obtain accurate results.

(b)i. Define the potential difference between two points in an electric circuit.

ii. Explain why the emf of a cell is greater than the p.d. across the call when it is supplying Current through an external resistance.