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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^\circ. 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^\circ 50^\circ 60^\circ and 70^\circ 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.

Measure and record the e.m.f of the accumulator provided. Connect the circuit as shown in the diagram. With zero resistance in the resistance box, adjust the rheostat to obtain the maximum possible reading on the ammeter. Do not adjust the rheostat again throughout the experiment. Open the key. With R= 1\(\Omega\), close the key, read and record the reading of the ammeter I. Calculate 1\(^{-1}\) Repeat the experiment for R=2,3,4 and 5\(\Omega\) respectively. In each case, read and record the value of \(1_A\) and calculate the Corresponding value of l\(_{A}^{-1}\). Now connect the resistor Q in series into the circuit and without altering the setting of the rheostat, record the new ammeter readings \(l_B\) for R= 1,2,3, 4, and 5\(\Omega\). Calculate the corresponding value of \(l_B\) in each case. Tabulate all your readings. On the same graph and using the same axes and scales, plot the graphs of: (i) I\(_{A}^{-1}\)' on the vertical axis and R on the horizontal axis; (ii) l\(_{B}^{-1}\) on the vertical axis and R on the horizontal axis. Calculate the slopes \(S_A\) in (i) and \(S_B\) in (ii) above. Determine the difference D between the intercepts of the graphs on the vertical axis. State two precautions taken to ensure accurate results. (b) i. Explain why a battery of eight dry Leclanche cells, each of e.m.f. 1.5v is not normally used in place of a motor-car battery of 12V to start a car. ii. State two sources of e.m.f. other than the chemical cell.

Which of the following is not a safety precaution in a nuclear station?

In each of the following sentences, there is one word underlined and one gap. From the list of words lettered A - D, choose the word that is most nearly opposite in meaning to the underlined word and that will, at the same time, correctly fill the gap in the sentences. To encourage productivity we must reward industry and ...........laziness

In each of the following sentences, there is one word underlined and one gap. From the list of words lettered A - D, choose the word that is most nearly opposite in meaning to the underlined word and that will, at the same time, correctly fill the gap in the sentences. I took the drug to relieve my headache only for it to...............my condition

In each of the following sentences, there is one word underlined and one gap. From the list of words lettered A - D, choose the word that is most nearly opposite in meaning to the underlined word and that will, at the same time, correctly fill the gap in the sentences. An optimist wears a smile most of the time but ...........goes about with a long face

In each of the following sentences, there is one word underlined and one gap. From the list of words lettered A - D, choose the word that is most nearly opposite in meaning to the underlined word and that will, at the same time, correctly fill the gap in the sentences. You will make a good counsellor by listening to your clients rather than........them

200cm\(^3\) each of 0.1M solutions of lead (II) trioxonitrate(V) and hydrochloric acid were mixed. Assuming that lead (II) chloride is completely insoluble, calculate the mass of lead (II) chloride that will be precipitated. [Pb = 207, Cl= 35.5, N = 14, O = 16]

56.00cm3 of a gas at S.T.P. weighed 0.11g. What is the vapour density of the gas? [Molar volume of a gas at S.T.P = 22.4dm3]

Which of the following gases will diffuse fastest when passed through a porous plug? [H = 1, C = 12, N = 14, O = 16]

Which is the temperature of a given mass of a gas initially at 0°C and 9 atm, if the pressure is reduced to 3 atm at constant volume?

Which of the following will have its mass increased when heated in air?

Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) From the equation above, the mass of magnesium required to react with 250cm3 of 0.5M HCl is [Mg = 24]

A gaseous metallic chloride MClx consists of 20.22% of M by mass. The formula of the chloride is? [M = 27, Cl = 35.5]