1. Using the spring balance provided, determine the weight of object of mass M = 5.0g. Record this weight as W\(_{1}\).
2. Determine the weight of the object when completely immersed in water contained in a beaker as shown in the diagram. Record the weight as W\(_{2}\)
3. Determine the weight of the object when it is completely immersed in the liquid labelled 'L'. Record the weight as W\(_{3}\). Evaluate, u = (W\(_{1}\) -W\(_{3}\)) and v = (W\(_{1}\) - W\(_{3}\)).
4. Repeat the procedure with the objects of masses M = 10, 15, 20, and 25g. In each case, evaluate u = (W\(_{1}\) - W\(_{3}\)) and v = (W\(_{1}\) - W\(_{3}\)) on the vertical axis against u = (W\(_{1}\) - W\(_{2}\) on the horizontal axis.
5. Determine the slope, s, of the graph. (vii) State two precautions taken to ensure accurate results.

(b)i. A piece of brass of mass 20.0g is hung on a spring balance from a rigid support and completely immersed in kerosine of density 8.0 x 10\(^{2}\)kg m\(^{-3}\). Determine the reading on the spring balance. [g= 10ms\(^{-2}\)], density of brass = 8.0 x 10\(^{3}\) kg m\(^{-3}\) J

ii. State Archimede's principle and the law of floatation.

1. Fix a metre rule on the bench with the graduated face up.
2. Place the illuminated object at the zero end of the rule and the screen at the other end as illustrated in the diagram above.
3. Measure and record D, the distance between the object and the screen. Evaluate D\(^{2}\).
4. Place and move the converging lens between the illuminated object and the screen until a diminished sharp image of the object is formed on the screen. Read and record the position, X\(_{1}\), of the lens. From this position, move the lens towards the object until another sharp image of the object is formed on the screen. Read and record the new position x\(_{2}\), of the lens.
5. Evaluate and record L (x\(_{1}\) - x\(_{2}\)), L\(^{2}\)) and (D\(^{2}\) - L\(^{2}\))
6. Repeat the procedure for D = 90, 80, 70 and 60 cm. In each case, evaluate, L L\(^{2}\) and (D\(^{2}\) - L\(^{2}\)). Tabulate your readings.
7. Plot a graph of D\(^{2}\) - L\(^{2}\) on the vertical axis against D on the horizontal axis.
8. Determine the slope, S, of the graph and evaluate K = \(\frac{s}{4}\). State two precautions taken to ensure accurate results.

(b)i. Distinguish between a real image and a virtual image.

Draw a ray diagram to show how a converging lens may be used to form a real diminished image of an object.

1. Measure and record the e.m.f. of the accumulator provided.
2. Connect a circuit as shown in the diagram. S is a standard resistor and R is a resistance box.
3. With R = 0\(\Omega\), close the key K. Read and record the ammeter reading I. Evaluate 1\(^{-1}\).
4. Repeat the procedure for R=1,2, 3, 4, and 5\(\Omega\). Tabulate your readings.
5. Plot a graph of R on the vertical axis and 1\(^{-1}\) on the horizontal axis, starting both axis from the origin (0,0).
6. Determine the slope s of the graph and find the intercept C on the vertical axis.
7. State two precautions taken to ensure accurate results.

(b)i. State two advantages of a lead-acid accumulator over a Leclanche cell.

ii. A parallel combination of 3\(\Omega\) and 4\(\Omega\) resistors is connected in series with a resistor of 4\(\Omega\) and a battery of negligible internal resistance. Calculate the effective resistance in the circuit.

In the diagram, a thread AC, fixed at pulley A passes over pulley C on a force board and carries an unknown mass m\(_{o}\). Retain this mass m\(_{o}\) throughout the experiment. Draw a line along the direction of AC on the paper held behind the thread. Locate the mid-point B of AC and mark its position on this line. Draw BP at right angles to AC. By means of a loop of thread, suspend a mass M 50 g from AC and adjust the position of the loop so that the line of action of the weight of M lies along with BP. Ensure that M and m\(_{o}\), hang off the force board. Measure BO = y and AO. Evaluate y / AO. Repeat the experiment for M = 70,90,110 and 130g respectively. In each case, determine the corresponding values of y, AO, and y / AO. Tabulate your readings. Plot a graph of Y/AO on the vertical axis and M on the horizontal axis. Determine the slopes s of the graph. State two precautions taken to ensure accurate results. Attach your traces to your answer script.

(b)i. Distinguish between the resultant and the equilibrant of forces.

ii. State two conditions necessary for the equilibrium of three non-parallel coplanar forces.

Trace the outline ABCD of the glass block on the sheet of paper as shown in the diagram. Remove the block and draw the normal at O. Draw an incident ray such that the angle of incidence i =30°. Fix two pins at points P and Q on the incident ray. Replace the block and fix two other pins at points U and V such that the pins appear to be in a straight line with the images of the pins at P and Q when viewed through the block. Remove the block and join the points at V and U, producing the line to meet DC at T. Join OT With O as a center and using any convenient radius, draw a circle to cut the incident and refracted rays at R and S respectively. Draw the perpendiculars RN and MS. Measure and record RN and MS. Repeat the experiment for i = 40° 50° 60° and 70° respectively. In each case, determine and record the corresponding values of RN and MS. Tabulate your readings. Plot a graph of RN on the vertical axis and MS on the horizontal axis. Determine the slope s of the graph, State two precautions taken to ensure accurate results. [Attach your traces to your answer script]

(b)i. Explain refraction.

ii. Draw a diagram showing why a metre rule, partly immersed in water and placed obliquely to the surface appears bent at the surface.