Find the values of unknown masses m and m . 1 2 Proceed as follows: (a) Clamp a metre rule vertically with the zero mark uppermost. Suspend the spring as shown in Figure 1 using a plasticine. Attach an optical pin to its lower end so that its point will move over the vertical scale. Read and record the scale reading X . o (b) Hang the mass = 50 g, to extend the spring. Read and record the new scale reading hence calculate the extension, e X  X 1 0 (c) Without removing the 50g mass and put the unknown mass m , repeat the 1 procedures in 1(b) for the values of mass m =100 g, 150 g, 200 g and 250 g to obtain a total of five readings, and calculate the extension in each observation. (d) Remove the last 250 g mass and put the unknown mass , record the new reading x 1 1 and the corresponding extension e X  X 1 0 (e) Replace m by m and repeat the procedure 1(d), record the reading x and the 1 2 corresponding extension e 2 Questions (i) Tabulate your results of m, x and e (ii) Plot a graph of mass (g) against extension e (cm). (iii) Find the slope S of the graph (iv) From the graph determine the unknown masses m1 and m 2 (v) State the physical meaning of the slope S.

1. Tabulate your results of m, x and e (5 mk)
2. Plot a graph of mass (g) against extension e (cm). (5 mk)
3. Find the slope S of the graph (5 mk)
4. From the graph determine the unknown masses m1 and m2 (5 mk)
5. State the physical meaning of the slope S. (5 mk)

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Determine the resistance per unit length  of the wire provided through the following procedures: (a) Set up the circuit as shown in the diagram below, where R is the resistance box, E is a dry cell, K is a key, G is a centre-zero galvanometer, J is a jockey and x is a wire of unknown resistance. (b) Measure the length x of the wire provided equal to 100 cm, fit it to the metre bridge as shown in Figure 2 .Close the key and slide a jockey over the resistance wire of the metre bridge until the galvanometer reads zero. Read and record L and its 1 corresponding L 2 (c) Repeat the procedures in 2(b) without changing the length x, setting R=2 Ω, 3 Ω, 4 Ω and 5 Ω and record the values for L and the corresponding values of L in each 1 2 case. L (i) Tabulate your results including the values of L 2 (ii) Plot a graph of R against L L 2 (iii) Compute the slope of the graph (iv) Determine the value for the resistance per unit length  of the wire provided. Show clearly how you arrive to your answer.

1. Tabulate your results including the values of L1/L2 (5 mk)
2. Plot a graph of R against L1/L2 (5 mk)
3. Compute the slope of the graph (5 mk)
4. Determine the value for the resistance per unit length  of the wire provided. Show clearly how you arrive to your answer. (10 mk)

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