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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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Question

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.
Numerical
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Solution

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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Chapter 14: Dual Nature of Radiation and Matter - Exercises [Page 322]

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Balbharati Physics [English] Standard 12 Maharashtra State Board
Chapter 14 Dual Nature of Radiation and Matter
Exercises | Q 8. | Page 322

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