ECAT Physics — Physics of Solids
Physics of Solids is part of the Physics section of the UET ECAT (30 of the 100 MCQs). It breaks into 3 subtopics, and we hold 16 ECAT-pattern practice MCQs on it, each with a written explanation. Tap a subtopic below to practise just that.
Subtopics (3)
How Physics of Solids is tested
Across the 7 ECAT past papers on ParhaiKrlo, Physics of Solids accounts for 4 questions. It appears in 3 of them, about 1.3 questions a paper. The heaviest was ECAT Past Paper 01, with 2 questions, and the most recent is ECAT Past Paper 03, with 1.
| Paper | Questions |
|---|---|
| ECAT Past Paper 03 | 1 |
| ECAT Past Paper 02 | 1 |
| ECAT Past Paper 01 | 2 |
Physics of Solids MCQs from the ECAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · ECAT Past Paper 03 · Physics of Solids
A material in which there is a very narrow energy gap between the conduction and valence bands is called a:
- A.Semiconductor
- B.Insulator
- C.Conductor
- D.Superconductor
Show answer
Answer: A. Semiconductor — Semiconductors have a small gap (~1 eV); insulators a large gap; in conductors the bands overlap (no gap).
- Q2 · ECAT Past Paper 02 · Physics of Solids
A semiconductor behaves as a(n) ______ at 0 K.
- A.Insulator
- B.Pure conductor
- C.Superconductor
- D.None
Show answer
Answer: A. Insulator — At 0 K no electrons have enough energy to cross the gap; the conduction band is empty, so it behaves as an insulator.
- Q3 · ECAT Past Paper 01 · Physics of Solids
The unit of longitudinal (tensile) strain is:
- A.m
- B.Unitless
- C.1/m
- D.None of these
Show answer
Answer: B. Unitless — Strain = ΔL/L, a ratio of two lengths, so it has no unit.