Heat energy is determined by how active the atoms or molecules are in a substance. The atoms and molecules in a hot substance move rapidly and seem excited while the molecules and atoms in a cool substance show less movement.Continue Reading
Heat energy also causes a substance to expand because the molecules need more space to move around in, and this is called thermal expansion. When a substance is cooled down, it will contract and be smaller than its original size. Linear expansion is the term use for rods or railway tracks where they will expand and become longer as they get warmer. Area expansion can be found in objects, such as engine pistons and the object becomes larger. Volume expansion can be seen in liquids as they become warmer.
Heat energy can transfer between objects. Conduction, convection and radiation are all terms use in heat transfer. Conduction is the action of heat transferring through solids, convection is the action of heat transferring through liquids and gasses, and radiation is heat transferred through visible and infrared light, such as that transferred by the sun.
Thermal equilibrium happens when a cool substance and a warm substance meet. The hot molecules loose energy to the cold molecules and they go back to having an energy level around the level they both started off at. Racecar drivers often leave their cars idling when cooling it down in order for all of the engine parts to reach thermal equilibrium.Learn more about Physics
Atomic bombs work by splitting atoms, while hydrogen bombs, also known as nuclear bombs, draw their energy from fusing atoms together. While both types of reactions involve the nucleus of the atom, and both can therefore rightly be called "nuclear," tradition has reserved the word for the types of reactions that are exclusive to fusion devices.Full Answer >
Explosions consist of a chemical reaction or a series of reactions in which a substance burns or decomposes very quickly, almost instantaneously, producing intense heat and gases that expand very rapidly. If the gas expansion is faster than the speed of sound in the air, the explosion produces a shock wave. Due to the rapid expansion, explosions apply force to surrounding objects and have the potential to cause damage.Full Answer >
The equation for the heat of fusion is ΔH=nΔHfus, where "n" is the number of moles and Δ is the molar heat of the substance. The heat of fusion is typically calculated in kilojoules and is represented in mathematical notation as "H."Full Answer >
Heat capacity is the amount of heat needed to change the temperature of a substance by 1 degree Celsius, while specific heat is the heat needed to change the temperature of 1 gram of substance by 1 degree Celsius. Whereas heat capacity is dependent on the amount of substance, heat capacity is independent of it.Full Answer >