As the thermal energy of matter increases, its particles usually spread out,
causing the substance to expand.
What is Thermal energy?
Thermal energy is the energy which is measured as a result of its heat
content. This is usually as a result of the increase in temperature of the
substance involved.
Increase in temperature leads to an increase in thermal energy. This leads
to the particles spreading out and the substance expanding as a result of
the atoms being loosely held together.
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