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X\(_L\) = 2\(\pi\)fL L = 7H, f = 50Hz X\(_L\) = 2 x 3.142 x 7 x 50 = 2199.40 \(\approxeq\) 2200\(\Omega\)

Impedance is a measure of how much a circuit opposes the flow of alternating current (AC). It combines both resistance (the real part) and reactance (the imaginary part) of a circuit component or network. Impedance is denoted by the symbol and is measured in ohms (\Omega).

At resonance, the inductive reactance (V\(_L\) ) equals the capacitive reactance (V\(_C\)), causing the voltages across the inductor and capacitor to be equal in magnitude but opposite in phase.

To calculate the energy of light, we can use the formula: E = h x f h = 6.63 x 10\(^{-34}\)Js f = 2.0 x 10\(^{15}\)Hz E = 6.63 x 10\(^{-34}\) x 2.0 x 10\(^{15}\) = 1.326 x 10\(^{-18}\)J

Energy of the emitted photon(E) = \(\frac{\text{hc}}{\lambda}\) \(\lambda\) = 5.68 x 10\(^{-6}\)m h = 6.63 x 10\(^{-34}\)Js c = 3.0 x 10\(^8\)ms\(^{-1}\) E =\(\frac{(6.63\times 10^{-34}) \times (3.0 x 10^8)}{5.68\times 10^{-6}}\) = \(\frac{1.989\times 10^{-25}}{5.68\times 10^{-6}}\) E = 3.50 x 10\(^{-20}\)J Therefore, the energy change = 3.50 x 10\(^{-20}\)J

Infrared thermometers work by detecting the infrared radiation emitted by objects. They measure this radiation to determine the object's temperature without direct contact.

A photometer is used to measure the intensity of light. Photometers can determine the brightness of light sources, compare light intensity from different sources, or measure the amount of light reaching a specific point. They are commonly used in photography, astronomy, and various scientific applications to ensure proper lighting conditions

A rectifier is a device that converts alternating current (AC) into direct current (DC). It enables the flow of current in one direction while blocking it in the opposite direction, thus transforming AC voltage into a form of DC voltage suitable for different applications.

Doping involves introducing specific impurities into a semiconductor to modify its electrical properties, enhancing its conductivity by creating either n-type or p-type semiconductors. Rectification is the process of converting alternating current (AC) into direct current (DC) using diodes, which allow current to flow in one direction. Emission refers to the release of charge carriers (electrons or holes) from a semiconductor, often resulting in the production of light in devices like LEDs Stabilization involves techniques to maintain the consistent performance of semiconductor devices under varying conditions.

Conductor: Has a very small or negligible band gap, allowing electrons to move freely. Insulator: Has a large energy gap (typically greater than 3 eV), which prevents electrons from jumping from the valence band to the conduction band, resulting in very low electrical conductivity. Semiconductor: A moderate energy gap (about 1 eV) allows some conductivity under certain conditions (like temperature or doping). Intrinsic Semiconductor: A type of semiconductor with a pure form, that also has a moderate energy gap similar to other semiconductors.

Observations show that when the light travels from a medium A(air) to a more dense medium B(water), the refracted ray bends towards the normal and the angle of refraction (r) is, therefore, less than the angle of incidence. vice versa.

Concave mirrors are designed to focus sunlight onto a specific area, enhancing the intensity of the solar energy. This concentrated energy can then be utilized for heating or converted into electricity in solar thermal and photovoltaic systems.

Concave Mirror: A concave mirror can focus light rays, allowing for a magnified image of the face. This magnification helps in seeing details more clearly, which is particularly useful for shaving. Convex Mirror: A convex mirror creates a smaller, wider image, which is not suitable for precise tasks like shaving. Plane Mirror: A plane mirror shows a true reflection but does not magnify, making it less effective for grooming. Parabolic Mirror: Parabolic mirrors are used for specific applications, like telescopes, but not for shaving.

Under red light, the shirt reflects the red light but does not reflect other colors, which makes it look less vibrant or pale, compared to being illuminated by white light that contains all colors.

Fiber optics: Fiber optics: Utilizes total internal reflection to transmit light through optical fibers, allowing for efficient data transfer.