# Semiconducter Devices And Circuit :-Semiconducter Assignment 1 Answers

Contents:-

## WEEK 1 – Excursion in Quantum Mechanics

In this blog we are providing semiconducter assignment 1 answers of NPTEL/SWAYAM. We will provide answers of every week of nptel courses.

### 1. The wave-function of the particle must be “normalizable”, because

a) the particle’s momentum must be conserved.

b) the particle can not exist at two places at the same time.

c)the particle must exist somewhere in the space.  (Answer)

d)the particle’s charge must be conserved.

a) (i)

b) (ii)

c) (iii)

(a) 2

(c) 5

(d) 2.5

a) 5.5 nm

b) 0.0039 nm

c) 3.9 nm

a) 0.225 nm

c) 22.5 nm

d) 0.02 nm

b) 1

c) 2/𝐿

d) √15 𝐿 −3/5

b) zero

c) 0.024

d) 0.0063

### ii) After passing through the slits what is the minimum spread in the electron’s momentum in the direction parallel to the plane of the slits and perpendicular to the average path of the electrons? Assume ℎ = 6.626 × 10−34 J.s and electron mass, m = 9.11 × 10−31 kg. Ignore any relativistic effect.

a) i) 1 V ii) infinity

b) i) 1 V ii) zero

c) i) 1.5 V ii) 10.54e-28 kg.m/s

### 9. The wave-function of a particle at state ‘n’ is given by, ψ(x) =  √ 3 cos( 2𝜋x /a ), |x| ≤ a/2              0, |x| > a/2   What is the average momentum of the particle at the state ‘n’?

(b) 6ℏ𝜋/a

(c) ℏ𝜋/a

(d) none of these

a) 0

b) (ℏ ^2)/ ma