Sarthaks APP
0 votes
3.8k views
in Physics by (38.1k points)

Consider a thin target (10–2m square, 10–3m thickness) of sodium, which produces a photocurrent of 100μA when a light of intensity 100W/m2 (λ = 660nm) falls on it. Find the probability that a photoelectron is produced when a photons strikes a sodium atom. [Take density of Na = 0.97 kg/m3].

1 Answer

0 votes
by (63.6k points)
selected by
 
Best answer

6 × 1026 Na atoms weighs 23 kg.

Volume of target = (10–4 × 10–3) = 10–7m3

Density of sodium = (d) = 0.97 kg/m 

Volume of 6 × 1026 Na atoms=23/0.97 m3=23.7 m 

Volume occupied of 1 Na atom

No. of sodium atoms in the target

Number of photons/s in the beam for 10–4 m2 = n

If P is the probability of emission per atom, per photon, the number of photoelectrons emitted/second

Thus the probability of photoemission by a single photon on a single atom is very much less than 1. (That is why absorption of two photons by an atom is negligible).

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...