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If p is the resistivity of a material, a...

If p is the resistivity of a material, and n is the number density of free electrons in it, the mean time between collisions between electrons in the material is given by: (m denotes the mass of an electron, and e denotes the charge on an electron)

A

`(n e^2p)/m`

B

`(me^2)/(np)`

C

`( mp)/(n e^2)`

D

`m/(n e^2p)`

Text Solution

AI Generated Solution

To find the mean time between collisions (τ) for electrons in a material given its resistivity (ρ) and the number density of free electrons (n), we can follow these steps: ### Step 1: Understand the relationship between drift velocity and electric field The drift velocity (V_d) of electrons in a conductor can be expressed as: \[ V_d = \frac{eE}{m} \tau \] where: - \( e \) is the charge of an electron, - \( E \) is the electric field, ...
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