A Certain Crystal Has a Spacing Of $0.442 \mathrm {~nm}$ Between Atoms

question 143

Multiple Choice

A certain crystal has a spacing of $0.442 \mathrm {~nm}$ between atoms. A beam of neutrons moving with a speed of $1640 \mathrm {~m} / \mathrm { s }$ perpendicular to the surface is diffracted as it passes through the crystal. What is the angle from the central maximum to the next interference maximum? ( $m$ neutron $= 1.675 \times$ $\left. 10 ^ { - 27 } \mathrm {~kg} , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

• A) \(21.0 ^ { \circ }\)
• B) \(90.0 ^ { \circ }\)
• C) \(33.1 ^ { \circ }\)
• D) \(17.0 ^ { \circ }\)
• E) \(60.0 ^ { \circ }\)

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Definitions:

Mucus

A slippery secretion produced by mucous membranes, serving to protect and lubricate surfaces.

Basement Membrane

A thin layer of extracellular matrix that separates epithelial or endothelial cells from the underlying connective tissue, providing support and regulation.

Hemidesmosomes

Specialized cell structures involved in the attachment of a cell to the extracellular matrix or basement membrane.

Adhesion Belt

A structure within epithelial cells, made of cadherin proteins, that helps in cell-cell adhesion, maintaining the structural integrity of tissues.