What is Heat?

Question

can anyone give me a scientific explanation please? : ( urgent project due tomorrow

Answer 1

This is one of those questions that is simple and complex at the same time. Everyone has felt heat, but what is it?

The simple answer is that heat is energy.

Heat travels in waves like other forms of energy, and can change the matter it touches. It can heat it up-which starts molecules moving or it can cause chemical reactions like burning to occur.

Heat can be released through a chemical reaction (such as the nuclear reactions that make the Sun "burn") or can be trapped for a limited time by insulators. It is often released along with other kinds of energy such as light, radio waves, or sound waves. A burning candle releases light and heat waves; an explosion releases light, heat, and sound waves. The Sun releases all kinds of energy waves

The heat energy of a substance is determined by how active its atoms and molecules are. A hot object is one whose atoms and molecules are excited and show rapid movement. A cooler object's molecules and atoms will be less excited and show less movement. When these guys are in the excited state, they take up a lot of space because they're moving around so fast. When the atoms and molecules settle down, or cool down, they take up less space.

Answer 2

Heat is molecules moving very quickly. It may surprise you to know that in a 75 degree Fahrenheit room, the average speed of an air molecule is a few hundred miles an hour. If you cool down the room, the average molecular speed slows down. If the room turns into an ice cube, the molecules don't move much at all, but they still do move. You need to get to absolute zero (270 degrees below zero Kelvin) to really stop molecules from moving. Even in solids, molecules have some movement, or vibration.

Heat is expressed as temperature. Temperature is directly related to pressure. If you take that same room and squeeze the air in it down to the size of a marble, say, the air will be very, very hot. This is why we have such high temperatures in the core of the sun. Because of all the gravitational weight of the sun bearing down on its center, the temperature gets to 10 million degrees Kelvin, just hot enough for nuclear fusion.

You feel heat because of these molecules zipping along and hitting your skin. If they are moving too fast, you will get burned. If they are moving too slow, they will cause the molecules in your skin to slow down and you will get frostbite.

Answer 3

The classical definition of heat is the flow of energy from a higher temperature "source" to a lower temperature "sink".

Answer 4

easy:

Heat - the lowest form of all energy. basically, heat is waste from energy.

got that one straight from my physics teacher in my classical mechanics class.

Answer 5

when u dont feel cold~