MCQ
The width of the $nth$ $HPZ$ will be
- A$\sqrt {nb\lambda } $
- ✓$\sqrt {b\lambda } \,[\sqrt n - \sqrt {n - 1} ]$
- C$(\sqrt n \, - \,\sqrt {n - 1} )$
- D$\frac{{\sqrt {b\lambda } }}{{[\sqrt n \, - \sqrt {n - 1} ]}}$
✓
Answer
Correct option: B.
$\sqrt {b\lambda } \,[\sqrt n - \sqrt {n - 1} ]$
b
(b)Width of $nth$ $HPZ$ ${B_n} = {r_n} - {r_{n - 1}}$
${r_n} = \sqrt {nb\lambda } $, ${r_{n - 1}} = \sqrt {(n - 1)b\lambda } $
${B_n} = \sqrt {nb\lambda } - \sqrt {(n - 1)b\lambda } = \sqrt {b\lambda } \,[\sqrt n - \sqrt {(n - 1)} ]$
(b)Width of $nth$ $HPZ$ ${B_n} = {r_n} - {r_{n - 1}}$
${r_n} = \sqrt {nb\lambda } $, ${r_{n - 1}} = \sqrt {(n - 1)b\lambda } $
${B_n} = \sqrt {nb\lambda } - \sqrt {(n - 1)b\lambda } = \sqrt {b\lambda } \,[\sqrt n - \sqrt {(n - 1)} ]$
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