TEST OF PRACTICAL KNOWLEDGE QUESTION Measure and record the emf, V\(_{o}\) of the cell provided. Connect a circuit as shown in the diagram above. With the k...

TEST OF PRACTICAL KNOWLEDGE QUESTION

1. Measure and record the emf, V\(_{o}\) of the cell provided.
2. Connect a circuit as shown in the diagram above.
3. With the key, K closed vary the rheostat, Rh to obtain a current 1 = 0.20A. Read and record the corresponding value of the potential difference, V on the voltmeter.
4. Evaluate 1\(^{-1}\) and V\(^{-1}\).
5. Repeat the procedure for four other values of l = 0.25, 0.30, 0.35 and 0.40 A. Tabulate your readings.
6. Plot a graph V\(^{-1}\) on the vertical axis against 1\(^{-1}\) on the horizontal axis.
7. Determine the slope, s, of the graph
8. Evaluate s\(^{-1}\).
9. State two precautions taken to ensure accurate results.

 (b)i. Explain Ohmic conductor:

ii. Explain resistivity of the material of a wire.