Advertisements
Advertisements
प्रश्न
Obtain the expression for the current flowing through a conductor having number density of the electron n, area of cross-section A in terms of the drift velocity vd .
उत्तर
`1/N sum_(i = 1)^N V_i = 0`
`a = (-eM)/m`
`V_i = v_i - (eE)/m t_1`
`= 0 -(eM)/m τ = - (eE)/m τ`
`I Delta t = + n e A |V_d | Delta t`
`|j| = ( "ne" ^2)/m τ |E|`
APPEARS IN
संबंधित प्रश्न
Derive an expression for drift velocity of free electrons.
What is its relation with relaxation time?
Estimate the average drift speed of conduction electrons in a copper wire of cross-sectional area 2.5 × 10−7 m2 carrying a current of 1.8 A. Assume the density of conduction electrons to be 9 × 1028 m−3.
When electrons drift in a metal from lower to higher potential, does it mean that all the free electrons of the metal are moving in the same direction?
When a current is established in a wire, the free electrons drift in the direction opposite to the current. Does the number of free electrons in the wire continuously decrease?
Metals are good conductor of heat than insulator because
An electric bulb.is rated 220 v and 100 watt power consumed by it when operated on 'no volt is:-
Derive an expression for resistivity of a conductor in terms of the number density of charge carriers in the conductor and relaxation time.
The potential difference applied across a given conductor is doubled. How will this affect (i) the mobility of electrons and (ii) the current density in the conductor? Justify your answers.
Consider two conducting wires A and B of the same diameter but made of different materials joined in series across a battery. The number density of electrons in A is 1.5 times that in B. Find the ratio of the drift velocity of electrons in wire A to that in wire B.
