translational energy

physics

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July 14, 2026

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In physics, kinetic energy is the energy an object possesses due to its motion. This motion can be translational, rotational, vibrational, or a combination thereof.

Translational kinetic energy is calculated as half the product of an object's mass (m) and the square of its velocity (v), expressed as ( \frac{1}{2}mv^2 ). For rotating bodies, kinetic energy is determined by their moment of inertia (I) and angular velocity (( \omega )), using the formula ( \frac{1}{2}I\omega^2 ). When an object's speed approaches the speed of light, relativistic effects become significant, and the laws of relativity must be applied. The standard unit for kinetic energy is the joule.12

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gas
Internal energy
…in three-dimensional space, and this translational motion contributes (3/2)RT (per mole) to the internal energy E. For monatomic gases, such as helium, neon, argon, krypton, and xenon, this is the sole energy contribution. Gases that contain two or more atoms per molecule also contribute additional terms because of their internal…
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…in three-dimensional space, and this translational motion contributes (3/2)RT (per mole) to the internal energy E. For monatomic gases, such as helium, neon, argon, krypton, and xenon, this is the sole energy contribution. Gases that contain two or more atoms per molecule also contribute additional terms because of their internal…
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spectroscopy
General principles
In theory, the translational energy of molecules through space is also quantized, but in practice the quantum effects are so small that they are not observable, and the motion appears continuous. The interaction of electromagnetic radiation with these molecular energy levels constitutes the basis for electron spectroscopy, visible,…
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In theory, the translational energy of molecules through space is also quantized, but in practice the quantum effects are so small that they are not observable, and the motion appears continuous. The interaction of electromagnetic radiation with these molecular energy levels constitutes the basis for electron spectroscopy, visible,…
Read More