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Atoms are the building blocks of the universe. Everything in the universe is made of atoms—every star, every tree, and every animal. The human body is made of atoms. Air and water are made of atoms, too.
It is the movement of energy through a substance such as water or air and is transmitted in waves. Sound energy is caused by vibrations in solids, liquids or gases.
When hydrogen burns in the air, water is formed. Oxygen is the most abundant element in the Earth’s crust, waters, and atmosphere (about 49.5%). Sound travels about 4 times faster in water than in air. Wind and water both cause erosion to the earth, moving large amounts of sand and rock to tear down mountains and build new structures. Further ...
But at the birth of the Universe – that is, everything – the energy needed for the Big Bang must have come from somewhere. Many cosmologists think its origin lies in so-called quantum uncertainty, which is known to allow energy to emerge literally from nowhere.
25 Οκτ 2024 · Water pollution is the release of substances (such as chemicals or microorganisms) or energy (in the form of radioactivity or heat) into surface and subsurface waters to the point that the substances interfere with beneficial use of the water or with the natural functioning of ecosystems.
About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium , sulfur , sodium , chlorine , and magnesium .
Where does the energy that makes life possible come from? Humans obtain energy from three classes of fuel molecules: carbohydrates, lipids, and proteins.
