With the help of a neat diagram explain the working of a calorimeter.
Important Points to Remember in Chapter -1 - Heat from Tamil Nadu Board Standard Eight Science Solutions
1. Effects of Heat:
(i) Heat energy: The energy transferred from one body to another body due to a temperature difference between them.
(ii) Effects of heat: Heat transfer causes expansion, increases temperature and changes the state of the substance.
(iii) Melting, vapourisation, sublimation, condensation, freezing and deposition are the change of states that take place due to heat energy.
2. Transfer of Heat:
(i) The heat energy is transmitted from a hot body to a cold body by the process of
(a) Conduction
(b) Convection
(c) Radiation
(ii) Conduction: The process of transference of heat in the material bodies, without the actual movement of the particles of the medium.
(iii) Conduction is possible only in solids. Mercury is an exception, which is a liquid metal.
(iii) Convection: The process of transference of heat in the material bodies, due to the actual movement of the particles of the medium.
(iv) Land Breeze: Breeze which blows from the land towards sea at night in coastal regions.
(v) Sea Breeze: Breeze which blows from sea towards land in day time in coastal regions.
(vi) Radiation: The process of transference of heat from a hot body to a cold body, without the aid of any external medium.
(vii) Radiant heat: The heat energy given out by hot bodies in the form of infrared rays.
3. Calorimetry:
(i) Calorimeter: A device which measures the heat capacity of liquids.
(ii) Calorimetry: The technique used to measure the amount of heat involved in a physical or a chemical process.
4. Thermostat:
(i) Temperature: Degree of hotness or coldness of a body.
(ii) Thermometer: A device used for recording temperature.
(iii) Celsius scale: A thermometric scale in which the length between melting point of ice and boiling point of water is divided into undefined equal parts is called degrees.
(iv) Heat capacity: Amount of heat energy required to raise the temperature of a substance by undefined or undefined.
(v) Specific heat capacity: Amount of heat energy required to raise the temperature of undefined kilogram of a substance by undefined or undefined.
(vi) Thermos flask: An insulating storage vessel that keeps its content hotter or cooler than the surroundings for a longer time.
(vii) Thermostat: Temperature sensing device that turns an appliance or circuit on or off when a particular temperature is reached in it.
