Heat Energy

It can be found everywhere because matter is found everywhere. It is heat energy. Heat energy results from the movement of atoms, molecules, and ions in solids, liquids, and gases. Heat energy is everywhere from volcanoes to sheets of ice and in the body. All matter contains heat energy. Heat energy can be transferred from one object to another due to the difference in temperature between the two objects. The difference is called heat.

For example, an ice cube and a glass of juice both have heat energy. When the ice cube is placed into the warmer glass of juice, the juice will transfer some its heat to the ice cube. The juice heats the ice cube. Eventually, the ice cube will melt, and the two substances will be the same temperature. When the same temperature is reached it is called thermal equilibrium.

Matter makes up everything in the universe, has mass and volume, takes up space, and exists either as a solid, liquid, or gas. Tiny particles called atoms, molecules, and ions make up the matter, and the particles are constantly in motion, vibrating back and forth. The movement of the particles creates a form of energy which is called heat or thermal energy.

The particles in solids are tightly packed together and only vibrate, in liquids, they vibrate and move around and slide into each other, and in gases, the particles move freely and rapidly with random motion.

The higher the temperature the more energy the particles will have. The energy can then easily be transmitted to other particles that are at a lower temperature. For example, a gas has fast-moving particles that can combine with slower moving particles. A transfer of energy takes place to the slower moving particle which increases the speed of that particle. As the collision of particles occurs, an area of high energy will slowly transfer across the material until thermal equilibrium is reached.

The fast-moving particles can rouse the nearby particles, and if heated sufficiently, the movement of particles in a solid increase and overcomes bonds that hold the particles together. The substance can then change from a solid to a liquid; in other words, it melts. If there is a further increase in the particles, the melted substance can then reach a stage where the substance changes into a gas; in other words, it evaporates.

There are three ways of transferring heat energy: convection, conduction, and radiation. Convection transfers heat energy through gases and liquids. Air is heated, the particles gain heat energy and allow the particles to move faster and further apart. The movement eventually creates a circular flow called a convection current. A convection current is used to heat a room using a radiator.

Conduction transfers energy into solids. The moving particles of a warm solid increase heat energy of particles in a cooler material. Since particles are closer together, solids conduct heat better than liquids or gases. An example is a fire used to ignite a candle; the fire spreads the heat through a solid material.

Finally, radiation is a method of heat transfer that does not require a particle to carry the heat energy. Heat is transferred in infrared waves, which is part of the electromagnet spectrum. Heat is released or radiates from all directions from the hot objects. When this happens, the heat energy carried by the waves can either be absorbed or reflected. The heat produced by the Sun is transferred to the Earth by radiation.

In summary, heat energy results from the movement of atoms, molecules, and ions in solids, liquids, and gases. There are three ways of transferring heat energy, convection, conduction, and radiation.




A: Equilibrium
B: Convection
C: Radiation
D: Conduction

A: Liquids
B: Solids
C: Gases
D: All the above

A: Two substances' temperatures remain the same during transfer of heat energy
B: The temperatures of substances never change during the transfer of heat
C: All substances will eventually reach the same temperature
D: Two substances reach equal temperatures during the transfer of heat energy

A: Radiation
B: Convection
C: Conduction
D: Both A and B

A: Atoms
B: Ions
C: Cells
D: Molecules

A: Radiation
B: Convection
C: Conduction
D: Equilibrium








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