The value of Planck's constant is:
Correct answer: D. 6.6262x10-34 J.sec
- A. 6.6262x10-30 J.sec
- B. 6.6262x10-32 J.sec
- C. 6.6262x10+34 J.sec
- D. 6.6262x10-34 J.sec
Explanation
Planck's constant is 6.626 times 10 to the minus 34 joule seconds, and its extreme smallness is why quantisation is invisible in everyday life and only matters at atomic scale. The positive exponent in one option would make it enormous, which a moment's thought rules out. It appears in E equals hf, in the de Broglie relation and in the uncertainty principle.
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About Planck's Quantum Theory
Planck's quantum theory states that energy is emitted or absorbed in discrete packets called quanta, with each packet having energy E = hν. It covers the meaning of Planck's constant, the relationship between frequency and wavelength, and how quantisation differs from the classical continuous model of energy.
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