Find the number of photons emitted per second from of source of light which results in a photocurrent with drift velocity of $1.5\ m/s$ in a conductor with cross-section area $0.25\ m^2$ , volume density of electrons $10^{20}\ per \ m^3$ , (Assume that $60\%$ of photons emitted result in electron emission)
Medium
Download our app for free and get started
$ \mathrm{i}=\mathrm{neAV}_{\mathrm{d}} $
$ \Rightarrow \frac{{{{\rm{n}}_{\rm{e}}} \times {\rm{e}}}}{{\rm{t}}} = {10^{20}} \times 1.6 \times {10^{ - 19}} \times 0.25 \times 1.5$
$= 16 \times \frac{1}{4} \times \frac{3}{2}=6 $
$ \Rightarrow \frac{\mathrm{n}_{e}}{\mathrm{t}}=\frac{6}{1.6 \times 10^{-19}} $
$ \Rightarrow \frac{{{{\rm{n}}_{\rm{p}}}}}{{\rm{t}}} = 6.25 \times {10^{19}}\,$ [ Given ${{\rm{ }}\frac{{{{\rm{n}}_{\rm{p}}}}}{{\rm{t}}} \times 60\% = \frac{{{{\rm{n}}_{\rm{e}}}}}{{\rm{t}}}}$]
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1The figure shows a network of five resistances and two batteries The total electrical power consumed by the circuit is ............... $W$View Solution
- 2A button battery is rated $3 \,V$ and $225 \,mAh . A$ cricket ball (mass $=0.163 \,kg$ ) having energy equal to that stored in the battety will have speed closest to ............ $\,m / s$View Solution
- 3View SolutionA potentiometer is an ideal device of measuring potential difference because
- 4In the adjoining circuit, the battery $E_1$ has an $e.m.f.$ of $12\, volts$ and zero internal resistance, while the battery $E_2$ has an $e.m.f.$ of $2\, volts$. If the galvanometer $G$ reads zero, then the value of the resistance $X$ in $ohms$ isView Solution
- 5Assertion : All electric devices shown in the circuit are ideal. The reading of each of ammeter $(a)$ and voltmeter $(V)$ is zero.View Solution
Reason : An ideal voltmeter draws almost no current due to very large resistance, and hence $(V)$ and $(a)$ will read zero.
- 6View SolutionIn the below circuit the current in each resistance is
- 7The current $I_{1}$ (in $A$) flowing through $1\; \Omega$ resistor in the following circuit is:View Solution
- 8Two resistances are joined in parallel whose resultant is $\frac{6}{8}\,ohm$. One of the resistance wire is broken and the effective resistance becomes $2\,\Omega $. Then the resistance in ohm of the wire that got broken wasView Solution
- 9A strip of copper and another of germanium are cooled from room temperature to $80\, K$. The resistance ofView Solution
- 10In the circuit shown in figure, the $5\,\Omega $ resistance develops $20.00\,cal/s$ due to the current flowing through it. The heat developed in $2\,\Omega $ resistance (in $cal/s$ ) isView Solution
