Bellringer You walk into the bathroom in your bare feet. The temperature in there is 23°C. You step onto the tile floor, and it feels very cold. Quickly, you step onto a throw rug, and the rug feels warmer. Is the floor really colder than the rug? Why do they seem to be at different temperatures when your bare feet touch them? Write your answers in your science journal.

Heat-notes You might think of the word heat as having to do with things that feel hot, but heat also has to do with things that feel cold.

Compare conduction, convection, and radiation. Objectives Define heat as thermal energy transferred between objects at different temperatures. Compare conduction, convection, and radiation. Use specific heat capacity to calculate heat.

Heat Heat is the energy transferred between objects that are at different temperatures. When two objects at different temperatures come into contact, energy is always transferred from the object that has the higher temperature to the object that has the lower temperature. Warm cCold

Thermal energy What is thermal energy? Thermal energy is the motion of particles in matter. Thermal means “heat” . We feel the thermal energy of particles in matter as heat. When you add thermal energy to matter the particles move faster. Something at a high temperature has more thermal energy than it would have at a lower temperature.

Thermal energy The more particles there are in a substance at a given temperature, the greater the thermal energy of the substance is. A bathtub full of water at 100oF has more thermal energy than a thimble of water at 100oF. The temperature is the same but the total amount of energy is different. The bathtub has more energy

Thermal energy When objects that have different temperatures come into contact, energy will always be transferred. Energy will pass from the warmer object to the cooler object until both have the same temperature. Do this…put your hand on a cold part of the table and leave it there until I tell you to move it.

Compare conduction, convection, and radiation. Objectives Define heat as thermal energy transferred between objects at different temperatures. Compare conduction, convection, and radiation. Use specific heat capacity to calculate heat.

Transferring Thermal Energy How is Thermal Energy Transferred? YOU MUST KNOW THIS!!!!! Conduction – direct contact Convection – through a fluid or gas Radiation – by electromagnetic waves

Conduction Thermal conduction is the transfer of thermal energy from one substance to another through direct contact. Heat transfers as particles of an object increase their collisions as heated. These collisions transfer the heat energy through the object by colliding with adjacent particles.

Conduction Thermal energy is transferred from the higher-temperature substance to the lower-temperature substance. Warm cCold This transfer makes some particles slow down and other particles speed up until all particles have the same average kinetic energy. The substances then have the same temperature.

Conductors and Insulators Substances that conduct thermal energy very well are called thermal conductors. Substances that do not conduct thermal energy very well are called thermal insulators. Conductors Insulators Curling iron Oven mitt Cookie sheet Plastic spatula Copper pipe Fiberglass insulation

Compare conduction, convection, and radiation. Objectives Define heat as thermal energy transferred between objects at different temperatures. Compare conduction, convection, and radiation. Use specific heat capacity to calculate heat.

Convection Convection the transfer of thermal energy by the movement of a liquid or a gas. Convection currents are caused by heating of a liquid or gas, the liquid or gas rises, then cools and falls. This occurs in the mantle of the earth, in the oceans and in the atmosphere. Most of our weather patterns are the result of convection currents in the atmosphere.

Convection The repeated rising and sinking of water during boiling are due to convection.

Radiation Radiation, the transfer of energy by electromagnetic waves, such as visible light and infrared waves. These wave may pass through all states of matter and also through NO matter – such as the vacuum of space.

Radiation The atmosphere traps the sun's energy because of greenhouse gases, such as water vapor, carbon dioxide, and methane, which trap energy especially well.

Greenhouse Effect Section 2 What Is Heat? Click below to watch the Visual Concept. Visual Concept

Heat and Temperature Change Thermal conductivity is the rate at which a substance conducts thermal energy. Some objects conduct thermal energy easily while others do not. Remove your hand from the table. Now touch the table with your other hand in the same spot. Now a different spot on the table where no ones hand was.

Compare conduction, convection, and radiation. Objectives Define heat as thermal energy transferred between objects at different temperatures. Compare conduction, convection, and radiation. Use specific heat capacity to calculate heat.

Specific Heat When equal amounts of energy are transferred to or from equal masses of different substances, the change in temperature for each substance will differ. Specific heat is the amount of energy needed to change the temperature of 1 kg of a substance by 1°C. The higher the specific heat of something is, the more energy it takes to increase its temperature.

What is heat? Heat is thermal energy that flows from something at a higher temperature to something at a lower temperature. What is specific heat? Specific heat is a property of matter which determines how readily a material is to absorb heat and change temperature. Specific Heat is defined as the amount of heat energy needed to raise the temperature of 1 kg of a substance by 1 oC or 1 K.

Measuring Heat Unlike temperature, energy transferred between objects can not be measured directly. Instead, it must be calculated. If you know an object's mass, its change in temperature, and its specific heat, you can use the equation above to calculate heat.

Brain pop!