Tag: science & technology

Diamond is the hardest known natural material on the Mohs scale of mineral hardness (10 out of 10). Graphite is soft and used in pencils, talc is the softest mineral (1 on Mohs scale), and calcite has a hardness of 3. Diamond's hardness comes from its strong covalent bonds between carbon atoms.

Speed is defined as distance traveled per unit time (s = d/t), measuring how quickly an object moves. Velocity includes direction as well, force causes acceleration, and energy is the capacity to do work. Speed specifically answers 'how fast' without regard to direction.

Lipids are organic compounds that include fats, oils, waxes, and certain vitamins. The term 'fats' is the most common everyday name for lipids in food and nutrition contexts. Salts are ionic compounds, germs are microorganisms, and 'Norcotics' is a misspelling of narcotics (drugs).

Pluto takes approximately 248 Earth years to complete one orbit around the Sun due to its great distance. Mercury orbits in 88 days, Venus in 225 days, and Uranus in 84 years. Pluto's long orbital period is one reason it was reclassified as a dwarf planet.

Soyuz (spacecraft), Vostok (first human spaceflight program), Salyut (space station program), and Venera (Venus exploration program) were all Soviet space programs during the Space Race era. These are not related to Egyptian mythology, Polish festivals, or Japanese space exploration.

Molecules are composed of atoms (A), which are the smallest units of matter that retain chemical properties. Particles is too general, compounds are made of atoms, and elements are specific types of atoms defined by proton count.

Daniel Fahrenheit (D) invented both the mercury thermometer (1714) and the alcohol thermometer earlier in 1709. James Watt worked on steam engines, Michael Faraday discovered electromagnetic induction, and Louis Pasteur pioneered pasteurization.

Saturn (B) has the highest wind speeds in the solar system, reaching up to 1,800 km/h in its equatorial region. Uranus, Venus, and Jupiter do not have winds as extreme as Saturn's.

Absolute zero is zero degrees Kelvin (C), which equals -273.15°C or -459.67°F. It is the lowest theoretically possible temperature where all thermal motion ceases.

An LDR (Light Dependent Resistor) is a photoconductive cell whose resistance decreases when light intensity increases. When photons strike the semiconductor material, they create electron-hole pairs, increasing conductivity and thus reducing resistance.