The average time that elapses between two successive collisions of an electron is calleda)Drift velocityb)Free timec)Relaxation timed)Collision timeCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

Relaxation time is the time interval between two successive collisions of electrons in a conductor, when current flows.

I = nave --> n->no. of free electrons a->area of conductor v->drift velocity e->charge of electron

but v=(eE/m)T--> E-> field m->mass of electron T->Relaxation time

From this, you can find expression of relaxation time.Field is V/length and V=IR.From this you can modify the expression in terms of resistivity.

Answer

Answer

Explanation:

Relaxation time is the average time between two successive collisions of an electron in a material. It is denoted by τ and measured in seconds.

When an electric field is applied to a material, electrons start moving in the direction opposite to the field. However, the motion of electrons is not smooth. They collide with atoms and molecules in the material and change their direction. The relaxation time is the time between two successive collisions of an electron.

Importance of Relaxation Time:

The relaxation time is an important parameter in the study of the electrical properties of materials. It determines the drift velocity of electrons, which is the average velocity of electrons under the influence of an electric field.

The relaxation time also determines the conductivity of a material. The higher the relaxation time, the lower the conductivity of the material.

In addition, the relaxation time is related to the mobility of electrons in a material. The mobility is the ratio of the drift velocity to the electric field. It is proportional to the relaxation time.

Conclusion:

In conclusion, the relaxation time is the average time between two successive collisions of an electron in a material. It is an important parameter in the study of the electrical properties of materials and determines the drift velocity, conductivity, and mobility of electrons.

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