TRIBHUVAN UNIVERSITY
INSTITUTE OF SCIENCE AND TECHNOLOGY
2080 B.S.
Candidates are required to give their answers in their own words as far as practicable.
Group A
Long Answer QuestionsAttempt any Two questions.
- 1Distinguish rigid and non-rigid body. Derive rotational kinetic energy expression and conservation conditions. A wheel ($r=0.4$m, $I=1.2\text{ kg}\cdot\text{m}^2$) with $2$-kg weight descending $1.5$m: find rotational velocity. (10)
- 2Setup Schrödinger equation for Hydrogen atom using spherical polar coordinates. Separate radial and angular parts. Discuss separation constant and quantum numbers. (10)
- 3What are RTL and TTL gates? How memory and clock circuits can be made by using these gates? Show and explain working scheme. (10)
Group B
Short Answer QuestionsAttempt any Eight questions.
- 4Describe classical free electron model. (5)
- 5How electric and magnetic fields are incorporated in electromagnetic wave? Explain. (5)
- 6Describe IC production processes: (a) Oxidation (b) Doping. Explain Photolithography in brief. (5)
- 7Oscillating block ($250$g, $0.2$s between $50$cm endpoints): find frequency, amplitude, and spring force constant. (5)
- 8Alpha particle ($q=3.2 \times 10^{-19}$ C, $m=6.70 \times 10^{-19}$ kg) released across $100$V potential: find its velocity at the plate. (5)
- 9Calculate uncertainty in momentum of an electron if position uncertainty is $1\text{ Å}$ ($10^{-12}$ m). (5)
- 10Hall voltage calculation: $50$A current in copper slab ($0.5$cm thick, $2$cm wide) in $1.5$T field. (5)
- 11Find length of unit cube for Sodium (BCC structure, density $0.971\text{ g/cm}^3$, atomic weight $23\text{ g/mole}$). (5)
- 12Draw circuit and find truth table for digital output $y = (C + B'A)(A+B+D)'$. (5)