Why isn't it possible to measure the thermal energy of a substance using a thermometer

The materials of thermometer that are designed to measure temperature only. Therefore, it is not possible to measure thermal energy.

Thermal Energy of a system is defined as the total kinetic energy possessed by the system. And temperature of a system is termed as the measure of average of kinetic energy of particles within the system.

Temperature is generally measured by Thermometers. And it is not possible to measure thermal energy due to following reasons:

Thus, thermometers are only used for the purpose of measuring temperatures, rather than thermal energy due to its design specifications.

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This is because a thermometer is designed to measure the temperature of a substance.

Explanation:

A thermometer is a device which is used to measure the temperature of a body which is known as the measure of the degree of the hotness or coldness of a body.

Temperature is measured in degree Celsius or Kelvin and it is entirely different from thermal energy which is measured in Joules.

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