A silicon block at 300,K has a length of 10,c | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Given: Length $l = 10\,cm = 0.1\,m$,Area $A = 1 	imes 10^{-4}\,m^2$,Voltage $V = 2\,V$,Mobility $\mu = 0.14\,m^2V^{-1}s^{-1}$,Electron density $n

Vedclass · Accepted Answer

$6.72 	imes 10^{-7}\,A$

Vedclass · Answer

(D) Given: Length $l = 10\,cm = 0.1\,m$,Area $A = 1 	imes 10^{-4}\,m^2$,Voltage $V = 2\,V$,Mobility $\mu = 0.14\,m^2V^{-1}s^{-1}$,Electron density $n = 1.5 	imes 10^{16}\,m^{-3}$,Charge of electron $e = 1.6 	imes 10^{-19}\,C$.The current $I$ is given by $I = neAv_d$,where $v_d$ is the drift velocity.Since $v_d = \mu E$ and $E = V/l$,we have $v_d = \mu (V/l)$.Substituting this into the current equation: $I = neA \left( \frac{\mu V}{l} ight)$.$I = \frac{n e A \mu V}{l} = \frac{(1.5 	imes 10^{16}) 	imes (1.6 	imes 10^{-19}) 	imes (1 	imes 10^{-4}) 	imes 0.14 	imes 2}{0.1}$.$I = \frac{1.5 	imes 1.6 	imes 0.14 	imes 2 	imes 10^{16-19-4}}{10^{-1}}$.$I = \frac{0.672 	imes 10^{-7}}{10^{-1}} = 0.672 	imes 10^{-6} = 6.72 	imes 10^{-7}\,A$.

Similar Questions

On increasing the temperature of a conductor,its resistance increases because

$A$ copper wire of length $1 \,m$ and uniform cross-sectional area $5 \times 10^{-7} \,m^{2}$ carries a current of $1 \,A$. Assuming that there are $8 \times 10^{28}$ free electrons per $m^{3}$ in copper,how long will an electron take to drift from one end of the wire to the other?

Drift speed of electrons,when $1.5 \, A$ of current flows in a copper wire of cross-section $5 \, mm^2$,is $v$. If the electron density in copper is $9 \times 10^{28} \, m^{-3}$,the value of $v$ in $mm/s$ is close to (Take charge of electron to be $1.6 \times 10^{-19} \, C$).

Which particles are responsible for the conductivity of metals?

Assertion : The electric bulb glows immediately when the switch is on.
Reason : The drift velocity of electrons in a metallic wire is very high.

Vedclass Test Series

Exam Paper Generator

Online Exam Module