The latent heat of a substance is the heat required for an object to change states, also called a phase change. Generally speaking, values for latent heats are much higher than those for specific heat. This is also referred to as enthalpy. Ice and water have enormous latent heats associated with them, which is why snow takes so long to melt and water is used for cooking.
This is also important in keeping our planet comfortable to live on, and provides a fair amount of resistance to climate change. Explore the simulation below to get a physical intuition of how friction can increase thermal energy and turn macroscopic motion into microscopic.
When a substance heats up, the rise in temperature makes these particles move faster and bump into each other. Thermal energy is the energy that comes from the heated up substance.
The hotter the substance, the more its particles move, and the higher its thermal energy. The hot chocolate has thermal energy from its vibrating particles.
When you pour some cold milk into your hot chocolate, some of this energy is transferred from the chocolate to the particles in the milk. So what happens? Your hot chocolate cools down because it lost some of its thermal energy to the milk.
The tea has thermal energy from its vibrating particles. When you pour some cold milk into your hot tea, some of this energy is transferred from the tea to the particles in the milk.
As cold particles heat, they contain more energy and so vibrate and separate. Some matter changes from solid to liquid to gas as its particles heat, vibrate and separate. Boiling a kettle is an example of both thermal and kinetic energy. You may need to make sure which definition a teacher or book is using. The Kinetic Theory of Matter states that matter consists of atoms or molecules in random motion.
Those moving particles can transfer their kinetic energy to other nearby particles. The total kinetic energy of all the particles in an object make up the thermal energy of that object. See Temperature and Heat for more information on those subjects. The thermal energy of an object can be created or increased by chemical and nuclear reactions, as well as electrical effects.
Each releases or transfers energy that cause an object's internal particles to increase their motion and thus their kinetic energy. For example, some chemical reactions cause nearby molecules to accelerate, thus increasing the total thermal energy of the object.
Burning is a common form of a heat-producing chemical reaction. Nuclear reactions, such as nuclear fission or nuclear decay, give off high-speed particles that increase the thermal energy of a material. The resistance to the motion of electrons in an electrical circuit cause the wire's molecules to increase their kinetic motion, thus increasing the thermal energy of the wire.
As a result, the more molecules that are present, the greater the amount of movement within a given system which raises the temperature and thermal energy. Because of this, at a temperature of 0? C, the thermal energy within a given system is also zero. This means that a relatively small sample at a somewhat high temperature such as a cup of tea at its boiling temperature could have less thermal energy than a larger sample such as a pool that's at a lower temperature.
If the cup of boiling tea is placed next to the freezing pool, the cup of tea will freeze first because it has less thermal energy than the pool. Matter exists in three states: solid, liquid, or gas. When a given piece of matter undergoes a state change, thermal energy is either added or removed but the temperature remains constant. When a solid is melted, for example, thermal energy is what causes the bonds within the solid to break apart. Heat can be given off in three different processes: conduction, convection, or radiation.
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