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Cuts magnetic flux: According to Faraday's law, when a conductor cuts through magnetic field lines (flux), an e.m.f is induced.

When electricity is transmitted over long distances, power losses occur mainly due to the resistance of the transmission lines. These losses are proportional to the square of the current (I\(^2\)R losses). By using high voltage, the current can be kept low, significantly reducing these losses

The capacitance of a capacitor is given by: C = \(\frac{Q}{V}\) where Q = quantity of charges, and V = voltage Q = 30c and V = 5v C = \(\frac{Q}{V}\) = C = \(\frac{30}{5}\) = 6 farad

Electric field intensity (E) = \(\frac{\text{force}}{\text{charge}}\) = \(\frac{\text{F}}{\text{q}}\) Given: E = 1200Vm\(^{-1}\), q = 1.6 x 10 \(^{-19}\)C, m = 9.1 x 10\(^{-31}\)kg F = E x q F = 1.6 x 10\(^{-19}\) x 1200 = 1.92 x 10\(^{-16}\)N F = ma a = \(\frac{F}{m}\) = \(\frac{1.92\times 10^{-16}}{9.1\times 10^{-31}}\) \(\approxeq\) 2.11 x 10\(^{14}\)ms\(^{-2}\)

The energy stored in the capacitor = \(\frac{1}{2}\)\(\frac{q^2}{C}\) Where C = 2F, q = 3C = \(\frac{1}{2}\)\(\frac{3^2}{2}\) = \(\frac{9}{4}\) = 2.25J

Electric field intensity(E) = \(\frac{\text{Force}}{\text{charge}}\) = \(\frac{F}{q}\) q = 4\muC = 4.0 x 10\(^{-6}\)C F = 8N E = \(\frac{8}{4.0 \times 10^{-6}}\) = 2.0 x 10\(^6\)NC\(^{-1}\)

Combined capacitance in series = \(\frac{1}{C_T}\) = \(\frac{1}{C_1}\) + \(\frac{1}{C_2}\) The two capacitors have capacitance of 0.0003\muF and 0.0006\muF respectively \(\frac{1}{C_T}\) = \(\frac{1}{0.0003}\) + \(\frac{1}{0.0006}\) = \(\frac{0.0002 + 0.0001}{0.0006}\) \(\frac{1}{C_T}\) = \(\frac{0.0003}{0.0006}\) C\(_T\) = 0.0002\muF.

F = \(\frac{Kq_1q_2}{r^2}\) F = \(\frac{9 \times 10^9 \times (1.0 \times 10^{-6})^2}{(0.2)^2}\) = 2.25 x 10\(^{-1}\)N

If lamp S goes off, all other lamps will go off. This is because lamp S is required to complete the whole circuit.

A mica capacitor has mica as its dielectric material. Known for excellent stability, low loss, and high insulation resistance, they are used in precision applications, particularly in RF circuits and high-frequency settings.

A voltameter measures the amount of substance that is deposited during electrolysis, allowing for the study of the electrochemical process. It provides information about the quantity of electric charge passed through the electrolyte and the resulting chemical changes. Voltameter is also called an Electrolytic cell.

If a sheet of an insulating material (dielectric) is inserted between the plates of an air capacitor, the capacitance will increase. When a dielectric material is inserted: The permittivity \(\epsilon\) increases (since the permittivity of the dielectric is greater than that of air), This results in an increase in capacitance.

The efficiency of a cell = \(\frac{\text{Ext. R}}{\text{Ext.R + int. r}}\) x 100 Ext. R = X int. r = 2\(\Omega\) Efficiency = 75% = 0.75 0.75 = \(\frac{\text{X}}{\text{X} + 2}\) 0.75( X + 2 ) = X 0.75x + 1.5 = X 0.25X = 1.5 X = \(\frac{1.5}{0.25}\) = 6\(\Omega\)

Faraday's second law states that the masses of different substances deposited or liberated by the same quantity of electricity are directly proportional to the chemical equivalents of the substances.

The capacitance of a capacitor, C, is inversely proportional to: Distance between plates: Capacitance decreases as the distance increases.