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Most capacitors contain at least two electrical conductors often in the form of metallic plates or surfaces separated by a dielectric medium.

In a DC generator, the coil rotates within a magnetic field, and the commutator is employed to convert the alternating current generated in the coil into direct current. The presence of the magnetic field, represented by the north (N) and south (S) poles, further confirms its identification as a DC generator.

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

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

By convention, the field direction is taken to be outward from the North pole and in to the South pole of the magnet. Also, they form closed lines.

Materials for making optical fibre are Glass, Polycarbonate, Teflon sheath, Silica, quartz, Silicon, Sapphire. Feromagnetic

Three classes of magnetic materials are (i) Diamagnetic (ii) Paramagnetic (iii) Feromagnetic

(a) An intrinsic semiconductor contains equal number of free electrons and holes. (b) p— TYPE n - TYPE i The majority carrier of electricity is holes. The majority carrier of electricity is electron. ii Carries a net positive charge Carries a net negative charge iii The impurity is trivalent The impurity is pentavalent.

Electric Field Intensity (E) = \(\frac{v}{d}\) = \(\frac{\text{potential difference}}{\text{distance}}\) = \(\frac{6.5v}{35cm}\) = \(\frac{6.5}{35 \times 10^{- 2}}\) = 18.57NC\(^{-1}\)

Internal resistance determine the maximum current that can be supplied Efficiency = \(\frac{R}{R+ r}\) \times 100 = \(\frac{6}{8}\) \times 100 = 75%

Resistor connected in a parallel have an equivalence given by \(\frac{1}{\text{Reff}}\) = \(\frac{1}{3}\) + \(\frac{1}{3}\) + \(\frac{1}{3}\) = \(\frac{1 + 1 + 1}{3}\) = \(\frac{3}{3}\) = 1 Reff = 1ω

The relationship between the peak value and r.m.s value of electricity supply is given as V\(_{r.m.s}\) = \(\frac{V_o}{\sqrt{2}}\) where Vo = peak voltage ∴ Vo = V\(_{r.m.s}\) × √2 = 240 × √2 = 339.5v = 340v

A d.c generator is one in which its current is allowed to flow in one direction even through it may vary in value an a.c generator can only be made to produce a d.c by replacing the two slip rings with a single split ring or commutator.

About electric cell Primary cells are used up gradually often the cells are use and it can't be recharged Secondary cells or accumulated can be recharged and used for a long period of time and their main advantage is that they have low internal resistance

V = IR from ohms law I = \(\frac{V}{R}\) Since the resistances are in parallel \(\frac{1}{Reff}\) = \(\frac{1}{18}\) + \(\frac{1}{12}\) + \(\frac{1}{6}\) = \(\frac{2 + 3 + 6}{36}\) = \(\frac{11}{36}\) R\(_{eff}\) = \(\frac{36}{11}\) = 3.27 I = I\(_1\) + I\(_2\) + I\(_3\) = \(\frac{V}{Reff}\)= \(\frac{12}{3.27}\) = 3.669A I = 3.7A