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M → \(\frac{Hi}{Ho}\) = \(\frac{Di}{Do}\) where M is the magnification, Hi is the height of the image, Ho is the height of the object, Di is the distance from the lens to the in-focus projected image, and Do is the distance from the object to the lens. But Di = \(\frac{Hi * Do}{Ho}\) → \(\frac{20 * 30}{40}\) Image distance(Di) = 15cm

Fiber optic couplers are used to split the input signals into two or more outputs, they are called splitters in this case. On the other hand, some types of couplers can be used to combine two or more inputs into one single output, they are called combiners in this case.

Eclipse of the moon occurs when the earth comes between the sun and the moon.

The angular wave number k = \(\frac{2\pi}{\lambda}\) expresses the number of radians in a unit of distance.

v = f \lambda to calculate the wave's velocity. v = 312 x 1.10 = 343.2m/s

Factors Affecting The Speed of Sound The Density of Medium: Sound requires a medium to travel. The density of the medium is among the factors which affect the speed of sound. ... The Temperature of The Medium: Higher the temperature, the higher is the speed of sound in the medium.

A helioscope is an instrument used for observing the sun and sunspots. The helioscope was first used by Benedetto Castelli and refined by Galileo Galilei.

Examples of Fundamental Quantities ; Mass, kilogram, kg ; Electric Current, ampere, A ; Temperature, kelvin, K ; Amount of Substance, mole, Mol.

A process called fractional distillation is used in oil refineries to separate (as well as join or split) the various lengths of hydrocarbon chains to create different petroleum products from the different distillates.

The nucleus contains two types of subatomic particles, protons and neutrons. The protons have a positive electrical charge and the neutrons have no electrical charge. A third type of subatomic particle, electrons, move around the nucleus.

The mass number = number of neutrons + atomic number. number of neutrons = The mass number - atomic number. number of neutrons = 37 - 17 = 20

The air in Earth's atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen. Air also has small amounts of other gases, too, such as carbon dioxide, neon, and hydrogen.

C \(\frac{69}{12}\) H \(\frac{15.3}{1}\) O \(\frac{30.7}{16}\) C = 5.75, H = 15.3, O = 1.92 C \(\frac{5.75}{1,92}\) H \(\frac{15.3}{1.92}\) O \(\frac{1.92}{1.92}\) C\(_3\)H\(_8\)O

Solid in gas mixture: Smoke, ice clouds, dust. Liquid in gas mixture: fog, mist, vapour and hair sprays. Gas in solid mixture: aerogel, Styrofoam.

A neutralization reaction is when an acid and a base react to form water and a salt and involves the combination of H+ ions and OH- ions to generate water.