Internal energy - thermodynamics, Mechanical Engineering

Assignment Help:

Internal Energy (U):

It is the energy possessed by the system on account of its configurations, and motion of atoms and molecules. Not like potential energy and kinetic energy of a system, which is visible and can be felt, internal energy is the invisible form of energy and can only be sensed. In thermodynamics, the major interest of study lies in knowing the change in internal energy than to know its absolute value.

The internal energy of a system is the sum of energies contributed by several configurations and inherent molecular motions. These contributing energies are given below

(1) Spin energy: because of clockwise or anticlockwise spin of the electrons about their own axes.

(2) Potential energy: because of intermolecular forces (Coulomb and gravitational forces), which keep molecules together.

(3) Transitional energy: because of movement of molecules in all the directions with all possible velocities within the system, this results in kinetic energy acquired by translatory motion.

(4) Rotational energy: because of rotation of molecules about the centre of mass of the system, resulting in kinetic energy acquired by the rotational motion. Such form of energy exists invariably in diatomic and polyatomic gases.

(5) Vibrational energy: because of vibration of molecules at the high temperatures.

(6) Binding energy: because of force of attraction between various sub atomic particles and nucleus.

(7) Other forms of energies such as Electric dipole and magnetic dipole energy when system is subjected to electric and magnetic fields. High velocity energy when rest mass of system mo changes to variable mass m according to Eisenstein's theory of relativity). The internal energy of system can increase or decrease during the thermodynamic operations. The internal energy will increase if the energy is absorbed and will decrease when energy is evolved out.

 


Related Discussions:- Internal energy - thermodynamics

State the main advantage of using master pages, Problem: (a) InDesign ...

Problem: (a) InDesign is known as a common software for designers mainly used for publication of newspapers, magazines and other editorial design artworks. The Master page fe

Find span of the beam, A beam is simply supported and carries a uniformly d...

A beam is simply supported and carries a uniformly distributed load of 40kn/m run over whole length or span. The section of the beam is rectangular having depth as 500mm. If the s

Evaluate the normal and tangential stresses, Evaluate the normal and tangen...

Evaluate the normal and tangential stresses: Q. 20: At the point in stressed body, the principal stresses are σ x = 80 kN/m 2 and σ y = 40  kN/m 2 . Determine the norma

Inlet channel of the exchanger, Q. Inlet channel of the exchanger? The ...

Q. Inlet channel of the exchanger? The inlet channel of the exchanger shall be designed to minimize flow turbulence and erosion of the refractory liner and the tube inlet area.

Thermodynamics, Two kg Ammonia (mA) at PA = 300 kPa and TA = -10ºC and 1 kg...

Two kg Ammonia (mA) at PA = 300 kPa and TA = -10ºC and 1 kg Ammonia (mB) at PB = 300 kPa and TB = 100ºC are mixed in a constant pressure and adiabatic process. Find the following:

Nominal stress and true stress, Nominal Stress and True Stress: Nomina...

Nominal Stress and True Stress: Nominal stress is the ratio of force per initial cross sectional area (original area of cross section). Nominal stress = Force / initial ar

Symmetric central force, Symmetric Central Force A central force is sph...

Symmetric Central Force A central force is spherically if the magnitude of the force does not depend on the direction (angles  θ , or  Ø ) of the particle but only on distance

Evaluate the natural frequency, (a) Evaluate the natural frequency of syste...

(a) Evaluate the natural frequency of system shown in figure and show that it will be equal to (b) calculate equivalent stiffness of two springs connected in parallel.

Mechanical data for line designation tables, Line Designation Tables (LDT's...

Line Designation Tables (LDT's) (Appendix "D") are initially generated by the Piping designers. Design conditions are inputed by the Process discipline, and the Mechanical Engineer

Refrigeration, A refrigeration system produces 40 kg/hr of ice at 0oC from ...

A refrigeration system produces 40 kg/hr of ice at 0oC from water at 25oC. Find the refrigeration effect per hour and TR. If it consumes 1 kW of energy to produce the ice,

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd