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No expanded working has been attached for this question yet. The verified answer is Option C.

Since the charged rod is not in contact with the electroscope, the leaves divergence will diverge.

IN magnetisation by stroking, the last touched has a pole opposite to that of the magnet used. Therefore, the poles T and V are N and N respectively

H eat generated in a wire carrying current, H = 12 Rt. so, when voltage is high and current is low heat generated in the wire will be minimal. Therefore, high voltage and low current prevent overheating of the coil.

C = C1 + C2 + C3 = 2 + 4 + 8 = 14\muF V = 6V Energy = 1/2CV2 1/2 x 14 x 10-6 x 62 = 2.52 x 10-4 J

pumping out of the gas in the discharge tube reduces the pressure inside the tube, therefore, electricity is conducted at low pressure

I = E/(R+r) = 12/6 = 2A

In Faradays law of electrolysis M = It = Q Where M is the mass of substance deposit . Q is the quantity of charge. A graph of m against Q is a straight line passing through the origin with slope equal to the electrochemical equivalent.Z

r = resistance of the galvanometer l = current through galvanometer = 1mA or 0.01A V1 = p.d across the galvanometer = I X r = 0.01 X r : V1 = 0.01r V2 = p.d across the multiplier = 5 - 0.01r R = resistance of the multiplier = 498\Omega where R = \(\frac{V}{I}\) --> 498 = \(\frac{5 - 0.01r}{0.01}\) CROSS MULTIPLY --> 498 X 0.01 = 5 - 0.01r 0.01r = 5 - 4.98 ∴ r = \(\frac{0.02}{0.01}\) = 2\Omega

Energy consumed = power x time = 200W x 24hr = 4800wh = 4.8 kwh But 1 kwh cost N40 ∴ 4.8kwh costs 4.8 x 40 = N192

Total inductance,L = L1 + L2 = m 15 + 5 = 20mH = (20)H/1000 1 = 5A Energy of inductor, (1)/2 L I2 = (1)/2 X (20)/1000 X 5-2 = 0.25 J

Resonance occurs whenever the phase angle of the circuit is zero, The only way that f = 0 is if XL = XC Note that tanϕ = \(\frac{ X }{ R}\) where X = reactance and ϕ = angle of lead or lag. therefore, tan ϕ = \(\frac{ X_L - X_C}{ R}\) but at resonance \(X_L = X_C\) tan ϕ = \(\frac{0}{R}\) = 0 and ϕ = \(tan^{-1}\) = 0º

∆E = hf f = (∆E)/h = (5.44 x 10-19)/6.6 x 10-34 = 8.24 x 1014

transistor serve the same purpose as triode valve, which is amplification of signals.

A semiconductor is a material whose conductivity is between good conductor and insulator. Example of pure semi conductors are silicon and germanium