An electron moving with velocity v has momentum 3 x 10 -26 Kg.m/s. The de Broglie wavelength associated with it is _. Value of h = 6.63 x 10^-34 is.
Correct answer: C. 22.1 nm
- A. 24.1 nm
- B. 22.14 m
- C. 22.1 nm
- D. 22.1 mm
Explanation
The de Broglie wavelength formula is λ = h/p, where h is Planck's constant and p is the momentum of the electron. Given the momentum p = 3 × 10-26 Kg.m/s and h = 6.63 × 10-34 J.s, substitute these values into the formula to find λ:λ = 6.63 × 10-34 / 3 × 10-26 = 22.1 nm.Option A is incorrect due to a calculation error. Option B is incorrect because it suggests a much larger and incorrect unit (meters). Option D is incorrect due to the wrong unit (millimeters). Thus, Option C is the correct answer with the correct units and calculation.
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Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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