Alchemy is the medieval forerunner of chemistry, concerned with the transmutation of matter, in particular with attempts to convert base metals into gold or find a universal elixir.
When you touch tea, you find that it’s hot. Similarly, when you touch ice, you find that it’s cold. But, how do you find out how hot or cold a substance is? The physical quantity that tells us how hot or cold a substance is, is known as Temperature. Temperature can be defined as-
Heat is transmissible. It flows from body to body. Transfer of heat takes place in all solids, liquids and gases. Heat transfer is possible only because particles like molecules and atoms that all matter is made up of.
The solar system comprises of a star and all the objects that travel around it- moons, planets, comets, asteroids, meteoroids etc. Solar systems can have more than one star called as binary star systems; with more than two stars they are known as multi-star systems.