Is praseodymium man made? He was correct about lanthanum being a new element, but he was wrong about didymium. This new “element” turned out to be a mixture of two other new elements, now called neodymium and praseodymium. The man who made this discovery was Auer. How was praseodymium named? Discovery: Swedish chemist Carl Gustav […]
How quick can evolution happen?
How quick can evolution happen? Across a broad range of species, the research found that for a major change to persist and for changes to accumulate, it took about one million years. How Fast Is human evolution? A study by anthropologists John Hawks, Henry Harpending, Gregory Cochran, and colleagues suggests that human evolution has sped […]
What is the universal system of measure?
What is the universal system of measure? The International System of Units (SI, abbreviated from the French Système international (d’unités)) is the modern form of the metric system. It is the only system of measurement with an official status in nearly every country in the world. What metric unit would you use to measure the […]
How many impact tests are there?
How many impact tests are there? There are basically two types of impact tests: pendulum and drop weight. Izod, Charpy, and tensile impact are the most common of the pendulum type tests. What is the difference between Charpy impact test and Izod impact test? In the Charpy impact test, the sample lies flat on the […]
What is amplitude of signal?
What is amplitude of signal? The amplitude of a variable is the measure of how far, and in what direction, that variable differs from zero. Thus, signal amplitudes can be either positive or negative. The time-domain sequences in Figure 1–3 presented the sample value amplitudes of three different waveforms. Is amplitude directly proportional to time? […]
Who discovered positive and negative charges?
Who discovered positive and negative charges? Benjamin Franklin What is charge and write its properties? The charge is a scalar quantity as it has only magnitude and no direction. The charge is just as other fundamental properties of the system like mass. The only difference between mass and charge is that charge is both positive […]
How do you bond valence electrons?
How do you bond valence electrons? Ionic bonds are formed through the exchange of valence electrons between atoms, typically a metal and a nonmetal. The loss or gain of valence electrons allows ions to obey the octet rule and become more stable. Ionic compounds are typically neutral. Therefore, ions combine in ways that neutralize their […]
What is lateral and longitudinal acceleration?
What is lateral and longitudinal acceleration? The longitudinal acceleration is in g force again similar to the lateral load transfer. The g force value is “Ax”. If you have acceleration in meters per second squared then the below equation can be used to convert it into units of g. If the longitudinal acceleration is due […]
What are 5 non-renewable resources?
What are 5 non-renewable resources? There are four major types of nonrenewable resources: oil, natural gas, coal, and nuclear energy. Oil, natural gas, and coal are collectively called fossil fuels. Fossil fuels were formed within the Earth from dead plants and animals over millions of years—hence the name “fossil” fuels. How can we save renewable […]