The first allowed FCC reflection is (111), so $d_{111}=a/\sqrt3$. Bragg’s law gives $d=\lambda/(2\sin\theta)$. Consequently $a=\sqrt3(0.1543)/(2\sin24.65^\circ)=0.3204$ nm, approximately 0.320, C. The supplied angle is θ, not 2θ.
More Materials characterization questions
GATE 2019 MT Q34– An FCC crystal of lattice parameter 0.3615 nm reflects monochromatic X-rays from (111)…
GATE 2019 MT Q40– In an SEM image, topographic information and atomic-number contrast are primarily obtained…
GATE 2026 MT Q15– During metallography, Nital is the most commonly used for etching .
GATE 2026 MT Q26– Residual stress present in a material can be determined by which one of the following…
GATE 2026 MT Q49– A metal with body-centered cubic structure is analyzed by X-ray diffraction using…
GATE 2025 MT Q17– In optical microscopy, which one of the following combinations of wavelength (λ) and…