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Aluminum has three valence electrons, while silicon has four. When aluminum is added to silicon, it creates "holes" (positive charge carriers) because there is one less electron to form a bond. These holes can move and carry charge, making the material p-type. Charge Carriers: Majority carriers in p-type semiconductors are holes. While, Arsenic (or other elements When doped into germanium (which has four valence electrons), the extra electron becomes free to move, which increases the number of negative charge carriers (electrons) in the material. This results in an n-type semiconductor. Charge Carriers: Majority carriers in n-type semiconductors are electrons

Since the cells are connected in parallel the net e.m.f is that of one cell, E. However the effective internal resistance should be added as parallel resistance. => 1/v + 1/25 + 1/25 + 1/25 = 1.2 ∴ v = 0.83Ω ∴ Effective e.m.f and internal resistance are respectively = 1.5V and 0.83Ω

The inductive reactance is given as Xl = 2πfl = 2 x 50/π x 0.1 = 10Ω Again from ohms law, R = V/I = 75/1.5 = 50Ω ∴ Thus the inductive reactance and the resistance are respectively 10Ω, and 50Ω

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

R = \(\frac{1}{2} + \frac{1}{2} + 3 = 1 + 3 = 4\Omega\)

\( R = \frac{\rho L}{A}\) \(\implies \rho\) = \(\frac{R.A}{L}\) = \(\frac{0.1 \times 3.14}{2} \left ( \frac{10^{-3}}{2} \right)^2\) \(\therefore\) \(\rho\) = \(\frac{0.1 \times 3.14 \times 10^{-6}}{2 \times 4}\) = 0.3925 x 10\(^{-7}\) OR 3.930 x 10 \(^{-8}\)\Omegam

A moving iron ammeter can measure both alternating current (AC) and direct current (DC) due to its design, which allows it to respond to the magnetic field created by both types of current.

(a) Electrolysis is the process of decomposing certain solutions or liquids or molten substances into their component parts by the passage of electricity through them. (b) Electrolyte is the solution or liquid or molten substance which will conduct electricity and which can be decomposed into its component parts during electrolysis. (c) Electrodes are the conductors in contact with an electrolyte through which current enters or leaves the electrolyte.

The charge of a body is determined by the imbalance between the number of protons (positively charged) and electrons (negatively charged). A deficiency of electrons results in a positive charge, while a surplus of electrons results in a negative charge.

In many AC radio circuits, transformers are used primarily to reduce the voltage to levels suitable for safe and effective operation of the components.

M = Itz; z = (M)/It = (2)/0.5 x 3 x 60 x 60 = 3.703 x 10-4 gc-1 ∴ M = Itz = 1.5 x 1 x 60 x 60 x 3.703 x 10-4 = 1.99962g. =2.0g

R\(_s\) = \(\frac{(i_gr_g)}{I-i_g}\) = \(\frac{(50 \times 10^{-3} \times 5)}{5 - (50 x 10^{-3})}\) = \(\frac{(0.25)}{4.95}\) = 0.0505 = 0.05Ω

Forward Biased Definition: A battery connection that allows current to flow across a p-n junction. Positive terminal to the p-type semiconductor and negative terminal to the n-type.Reduces the potential barrier, allowing charge carriers (holes and electrons) to move toward the junction and enabling current flow.

R = \(\frac{ \rho \times L}{A}\), \(\rho\) = \(\frac{R . A}{L}\) d = 1mm = 0.001m, r = 0.0005m A = \(\pi\)r\(^2\) = \(\frac{22}{7}\) x (0.0005)\(^2\) = 7.857 x 10\(^{-7}\) \(\rho\) = \(\frac{R . A}{L}\) = \(\frac{0.1 \times 7.857 \times 10^{-7}}{2}\) \(\rho\) = 3.928 x 10\(^{-8}\)\(\Omega\)m

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