Question

Match List-I with List-II.
 

List - I		List - II
A.	Surface Defects	I.	Vacancy
B.	Point Defects	II.	Dislocation
C.	Volume Defects	III.	Grain Boundary
D.	Line Defects	IV.	Crack

• A. A-III, B-I, C-IV, D-II
• B. A-I, B-II, C-III, D-IV
• C. A-II, B-III, C-IV, D-I
• D. A-IV, B-I, C-II, D-III

Hint:

Vacancy is a point defect, dislocation is a line defect, grain boundary is a surface defect, and crack is a volume defect.

Answer 1

The Correct Option is A

Concept:
Defects in solids are classified according to their dimensional nature. Point defects are zero-dimensional, line defects are one-dimensional, surface defects are two-dimensional, and volume defects are three-dimensional.

Step 1: Surface defects.
Surface defects are two-dimensional defects. Grain boundary is a common surface defect because it separates two grains having different orientations. \[ A\rightarrow III \]

Step 2: Point defects.
Point defects occur at atomic sites. Vacancy is a point defect because it represents a missing atom from its regular lattice site. \[ B\rightarrow I \]

Step 3: Volume defects.
Volume defects are three-dimensional defects. Crack is a volume defect because it extends through a finite volume of the material. \[ C\rightarrow IV \]

Step 4: Line defects.
Dislocation is a line defect because the irregularity extends along a line in the crystal. \[ D\rightarrow II \] Therefore: \[ A-III,\ B-I,\ C-IV,\ D-II \] \[ \therefore \text{Correct Answer is (A)} \]