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I = \(\frac{E}{R + r} = \frac{1.5}{5 + 1}\) = \(\frac{1.5}{6} = 0.25A\)

R = \(\frac{V^2}{P} = \frac{240^2}{120} = 480\Omega\)

(a) Applications of electrolysis: — Electrotyping — Electroplating — Purification of metals — Extraction of metals — Callibration of ammeter (b) It means that when a charge of one coulomb IC is passed through a copper voltameter 3.3 x 10\(^{-7}\) kg of copper is on the cathode.

(a)(i) Primary cell defects: — Polarization — Local action Polarization — This is due to hydrogen bubbles covering the positive electrode (copper plate). Local action — This is due to the use of impure zinc or the gradual wearing away of the negative electrode zinc plate. (ii) Advantages of secondary cell over a primary cell: — a secondary cell can be recharged while primary cell cannot. — secondary cell can supply current for a longer period while the primary cell has a short life-span. (b) (c)(i) The internal resistance of the dry cells is much larger than that of the accumulators, hence accumulators will produce larger currents needed to start the engine. (ii) Positive terminal Negative terminal Electrolyte Leclanche cell Carbon rod Zinc rod Ammonium chloride (NH\(_4\) charged lead acid accumulator Lead (IV) oxide or Lead peroxide Lead Lead Tetra oxo-sulphate (VI) acid (H\(_2\)SO\(_4\))

When the base current of a common-emitter transistor is zero, it operates in the cut-off region, meaning it does not conduct current. This region is essential for the transistor to act as an off switch in circuits.

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In a purely capacity circuit, voltage lags behind current by 90°, or current leads voltage by 90°

The electrons and cations of ionized gas act as charge carriers.

in a transformer, E S/E P = N s/N p where E s=e.m.f(voltage)of the secondary E p=e.m.f(voltage)of the primary N s=no.of turns in the secondary N p= no. of turns in the primary. since E s= V s; and E p= V p. V s/ V p= N s/N p ∴12/240= Ns/4000 Ns =(12x4000)/240 =200

the current in reverse biased junction diode is due to minority carriers, that is, the negative charges in the p-semi-conductor, and the positive charges in the n-semi-conductor.

Sodium is a soft, silvery-white metal that is a good conductor of electricity. It has free-moving electrons, which allows it to conduct electrical current efficiently

Magnetic poles always exist in pairs. It is not possible to produce just an isolated north pole or an isolated south pole. If a bar magnet is broken into two pieces, each piece will have a north and south pole.

For a car battery rated 45 AH, being charged by a charger of 2.5 A rating, the time for the battery to be fully charged is given by: T = (45)/2.5 = 18 hrs

The charge must be opposite in sign, since the positive charges will deflect to the negative plate, and the negative charge to the positive plate

The effective capacitance in the circuit is given by: 1/C = 1/2 + 1/3 + 1/6 = 6/6 therefore C = 1μF or 1.0 x 10-6F. Since C = Q/V, its implies that the charges Q, flowing in the circuit is given by Q = CV = 1.0 x 10-6 x 12 = 12.0 x 10-6 Coulomb. ∴ P.d across the 6μF, V = Q/C = 12.0 x 10-66.0 x 10-6F = 2.0 volts