My Father: the Person I Admire Most
HEAT 4.1 UNDERSTANDING THERMAL EQUILIBRIUM 1. Define: The measure of the degree of hotness of an object. (a) Temperature Measured in SI unit Kelvin, K A hot object is at a higher temperature than a cold object. Form of energy, measured in Joules, J (b) Heat Heat is transferred from hotter object (higher temperature) to colder object (lower temperature) When an object is heated, it will absorb heat energy and the temperature will increase. When an object is cooled, it will release heat energy and the temperature will decrease. (c) Thermal Two objects are in thermal contact when heat energy contact can be transferred between them. (d)Heat transfer When two objects with different degrees of hotness come into thermal contact, heat energy is transferred between the two objects. (e) Mechanism of Thermal Equilibrium
Energy is transferred at a faster rate from the hotter object to the colder object. Energy is also transferred from the colder object to the hotter one, but at a slower rate. There is a net flow of energy from the hotter object to the colder object. (f) Thermal When two objects are in thermal equilibrium, there is Equilibrium no net flow of heat between them. Two objects in thermal equilibrium have the same temperature
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The hotter object cools down while the colder object warms up . After some time, energy is transferred at the same rate between the two objects. There is no net heat transfer between the objects. The two objects are said to be in thermal equilibrium.
Example of thermal equilibrium A wet towel is placed on the forehead of a person who has high fever. Initially the temperature of the cloth is lower than the body temperature of the person. Heat energy is transferred from the forehead to the towel until thermal equilibrium is reached. The towel is rinsed in tap water and the procedure is repeated. In this way heat energy is removed from the person. Cooling drinks A hot drink can be cooled by adding a few ice cubes to the drink. Heat
Energy is transferred at a faster rate from the hotter object to the colder object. Energy is also transferred from the colder object to the hotter one, but at a slower rate. There is a net flow of energy from the hotter object to the colder object. (f) Thermal When two objects are in thermal equilibrium, there is Equilibrium no net flow of heat between them. Two objects in thermal equilibrium have the same temperature
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The hotter object cools down while the colder object warms up . After some time, energy is transferred at the same rate between the two objects. There is no net heat transfer between the objects. The two objects are said to be in thermal equilibrium.
Example of thermal equilibrium A wet towel is placed on the forehead of a person who has high fever. Initially the temperature of the cloth is lower than the body temperature of the person. Heat energy is transferred from the forehead to the towel until thermal equilibrium is reached. The towel is rinsed in tap water and the procedure is repeated. In this way heat energy is removed from the person. Cooling drinks A hot drink can be cooled by adding a few ice cubes to the drink. Heat