The candidates were expected to:
(i)set up a circuit as shown in the diagram above;
(ii)measure and record value of emf correctly to at least 1 decimal place in volt;
(iii)measure value of Vo and record to at least 1 decimal place in volts;
(iv)measure five values of V and record to at least 1 decimal place in volts and in trend.
Trend: R increases and V increases;

(v)evaluate five values of V-I correctly and record to at least 3 decimal places;
(vi)evaluate five values of R-1 correctly and record to at least 3 decimal places;
(vii)present data in a composite and complete table and showing R, V, R-1 and V-1;
(viii) correctly distinguish the graph axes, choose reasonable scales, plot the five points and draw a line of best fit into the points;
draw a large right angled triangle on the graph line, read ΔR-1 and V-1 and evaluate slope = ΔR-1
                                                                                                                                                                 ΔV-1
(ix)evaluate k = slope. to obtain a value within ± 10% of the emf of Intercept the battery used;
(x)state any two of the following precautions in acceptable form of speech:
-I ensured tight connections/clean terminals;
-I removed key when not taking readings;
-I avoided parallax error in reading voltmeter;
-Zero error of voltmeter corrected.
(b)(i)The four factors on which the resistance of a wire depend

(i)Temperature.
(ii)Length of the wire.
(iii)Cross section area of wire/diameter of wire•
(iv)Resistivity of the wire/type of wire.

          E = Irl + IR
Where r1 = the effective internal resistance of the two cells in parallel.
         i.e. r1 = r/2
          i.e. 2.0 = 0.8 [r/2+ 2]
         i.e. 2.0 = 0.4 + 1.6
           r = 2.0 - 1.6= 1.0                              

                0.4

The electricity experiment was the least popular of all the questions. The performance of the candidates' were satisfactory. The candidates were able to connect the circuit correctly. They were able to measure V and R and evaluate V­¹ and K1. They plotted good graphs and were able to determine the slope and intercept of the graph correctly.

The precautions were also correctly stated.
In part (b)(i) the candidates were able to recall the factors on which the resistance of a wire depends. The numerical in b(ii) was however not satisfactorily handled.