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Observations from an experiment on the photoelectric effect for the stopping potential by varying the incident frequency were plotted. The slope of the linear curve was found to be approximately

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प्रश्न

Observations from an experiment on the photoelectric effect for the stopping potential by varying the incident frequency were plotted. The slope of the linear curve was found to be approximately 4.1 × 10−15 V s. Given that Exercises the charge of an electron is 1.6 × 10−19 C, find the value of the Planck’s constant h.
संख्यात्मक
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उत्तर

Data: Slope = 4.1 x 10-15 V·s, e = 1.6 x 10-19 C

V0e = hv - hv0

∴ `"V"_0 = ("h"/"e")"v" - (("hv"_0)/"e")`

∴ Slope = `"h"/"e"`

∴ Planck's constant,

h = (slope)(e)

= (4.1 x 10-15 V·s)(1.6 x 10-19 C)

= 6.56 × 10-34 J.s `("as 1 V" = ("1J")/"1C")`

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अध्याय 14: Dual Nature of Radiation and Matter - Exercises [पृष्ठ ३२३]

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बालभारती Physics [English] Standard 12 Maharashtra State Board
अध्याय 14 Dual Nature of Radiation and Matter
Exercises | Q 8 | पृष्ठ ३२३

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