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The hertz is the unit of frequency of one cycle per second. symbol: hertz (Hz) Hertz in honor of the German physicist Heinrich Hertz hertz in the International System of Units (SI) frequency i s defined as one cycle per second ***
Explanation
Exponential notation (scientific notation) is used to express very small (e.g., 0.0000001) or very large (e.g., 1000000000) quantities compactly by representing numbers as powers of 10 . Key Information : Format : a × 10^n, where 1 ≤ a < 10 and n is an integer. Used for very large or very small numbers . Examples: Large number : 6.022 × 10^23 ( Avogadro's number ) Small number : 1.6 × 10^-19 ( Charge of an electron )
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Marconi invented Radio . Radio was invented in 1895 . Guglielmo Marconi was an Italian inventor. *****
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The Mole (mol) is the SI unit of amount of substance, representing 6.022 x 10^23 particles. It is used to measure the amount of a substance in a sample.
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Louis Pasteur (1822–1895) was a pioneering microbiologist and chemist whose work bridged both fields: As a Chemist : Discovered molecular chirality (optical isomers). Studied fermentation, proving it was caused by microorganisms. As a Microbiologist : Developed pasteurization (heat treatment to kill microbes in food). Created vaccines for rabies and anthrax. Disproved spontaneous generation (germ theory of disease).
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The chemical formula CH₃COOH represents acetic acid , a weak organic acid commonly found in vinegar. Key Information : Common Name : Acetic acid (systematic name: ethanoic acid). Properties : Weak acid (partially dissociates in water). Pungent smell, sour taste (vinegar contains ~4–8% acetic acid).
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Xylem and Phloem are specialized conducting tissues in vascular plants: Xylem : Transports water and minerals from roots to other parts (unidirectional). Phloem : Transports sugars (photosynthates) from leaves to other parts (bidirectional).
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The atomic weight of Mercury (Hg) is 200.59 unified atomic mass units (u), as listed on the periodic table. Key Information : Symbol : Hg (from Latin Hydrargyrum) Atomic Number : 80 Standard Atomic Weight : 200.592 u (often rounded to 200.59 u).
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The mass of Earth is approximately 6.0 x 10^24 kilograms ( 5.98 x 10^24 kg ). This is a widely accepted scientific value , based on various measurements and calculations, including: Gravity measurements Satellite orbits Seismological data Planetary formation models
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Longitudinal Wave (Primary Nature): Sound propagates as compressions and rarefactions (particles vibrate parallel to wave direction). Example: Sound waves in air. Mechanical Wave (Medium Dependency): Requires a medium (solid, liquid, gas) to travel—cannot propagate in a vacuum. Transverse Wave (In Specific Cases): In solids, sound can also exhibit transverse wave components (particles vibrate perpendicular to the wave direction).
