Kinetic Energy and Kelvin Temperature BY: MELVIN G. FLORES East Gadsden High School

What Will Be Covered Kinetic Energy Kinetic Energy Kelvin Temperature Kelvin Temperature How the Two Are Related How the Two Are Related The Kelvin Scale The Kelvin Scale

Kinetic Energy Kinetic energy is the energy an object has because of its motion Kinetic energy is the energy an object has because of its motion

Kelvin Temperature Kelvin Temperature, or absolute zero, is the temperature at which the motion of particles probably stops. Kelvin Temperature, or absolute zero, is the temperature at which the motion of particles probably stops.

How the Two Are Related An increase in the average kinetic energy of particles causes the temperature of a substance to rise. An increase in the average kinetic energy of particles causes the temperature of a substance to rise. As a substance cools, the particles move more slowly, and their average kinetic energy declines As a substance cools, the particles move more slowly, and their average kinetic energy declines Particles would have no kinetic energy at absolute zero because they would have no motion Particles would have no kinetic energy at absolute zero because they would have no motion

Continued… The following graph shows the distribution of kinetic energies at two different temperatures: The following graph shows the distribution of kinetic energies at two different temperatures:

Continued… The Kelvin temperature scale reflects the relationship between temperature and average kinetic energy. The Kelvin temperature scale reflects the relationship between temperature and average kinetic energy. The Kelvin temperature of a substance is directly equal to the average kinetic energy of the particles of a substance. The Kelvin temperature of a substance is directly equal to the average kinetic energy of the particles of a substance.

Heat Transfer When you touch a hot surface, there is a transfer of kinetic energy from the molecules in the hot surface to the molecules in your hand. If you touch ice, energy from the molecules in your hand to the molecules in the ice.

Heat  Energy is always transferred from a warmer substance to a cooler substance.  The energy that is transferred is called heat. Matter does not contain heat; matter contains energy, that when transferred from one substance to the next turns into heat.  When energy is transferred from one substance to the next, the substances are said to be in thermal contact.

Transfer of Energy  Heat will flow from the higher temperature substance to the lower temperature substance, not necessarily from a substance with more molecular kinetic energy (kinetic energy of molecules) to a substance with less molecular kinetic energy.  Energy will only be transferred when there is a difference in temperature, not a difference in kinetic energy.

1.) Does heat flow from a higher temperature substance to a lower temperature substance OR from a lower temperature substance to a higher temperature substance. 2.) When two substances are in contact, what type of energy is transferred from one substance to the other? 3.) What is the freezing point for water in degrees Celsius? What is the boiling point for water in degrees Celsius? 4.) When are two substances in thermal contact?

Conclusion Kelvin temperature effects the kinetic energy of a substance Kelvin temperature effects the kinetic energy of a substance If temperature increases, so does energy If temperature increases, so does energy At any given temperature the particles of all substances, regardless of physical state, have the same kinetic energy. At any given temperature the particles of all substances, regardless of physical state, have the same kinetic energy.

QUESTIONS?