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Master wave-particle duality, quantum mechanics, Einstein’s relativity, photoelectric effect equations, de Broglie wavelength formula, and nuclear half-life calculations with study notes and practice MCQs: wave-particle duality, photoelectric effect equations, de Broglie wavelength formula)
Special relativity rests on two postulates: (1) The laws of physics are identical in all inertial reference frames. (2) The speed of light in a vacuum (c = 3×10&sup8; m/s) is constant for all observers, regardless of the motion of the source or observer.
Consequences: time dilation (moving clocks run slow), length contraction (moving objects appear shorter in the direction of motion), and mass-energy equivalence: E = mc².
Understand photons, Planck’s constant ($E=hf$), and the equation for photoelectric effect with work function calculations: equation for photoelectric effect.
Master wave-particle duality, matter waves, and the de Broglie wavelength formula ($\lambda = h/mv$): wave-particle duality, de broglie wavelength formula.
Learn nuclear binding energy, alpha beta gamma decay equations, and how to find half life using exponential decay formulas: alpha beta gamma decay, how to find half life) photon emitted. All governed by E = mc².
Essential de Broglie equations, photoelectric formulas, mass-energy equivalence, and radioactive half-life formulas for exam revision. de Broglie equations, half-life formulas)
Unit: J (Joules)
Unit: J (Joules)
Unit: m (metres)
Unit: s (seconds)
Unit: J (Joules)
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Clear answers to key questions about wave-particle duality, photoelectric effect, and nuclear fission versus fusion
Einstein special relativity (1905) states that the speed of light is the same for all observers and that the laws of physics are identical in all inertial frames. Key consequences are time dilation, length contraction, and E = mc².
When light above a threshold frequency hits a metal, it ejects electrons. The energy of each electron depends on frequency (not intensity) of light. Einstein explained this by treating light as discrete photons with energy E = hf, winning the 1921 Nobel Prize.
All matter and radiation exhibit both wave and particle properties. Electrons interfere like waves (wave nature) but transfer energy in discrete packets (particle nature). The de Broglie wavelength λ = h/mv applies to all particles.
Fission splits a heavy nucleus (e.g. U-235) into smaller fragments, releasing energy. Fusion joins light nuclei (e.g. hydrogen isotopes) into a heavier nucleus, releasing even more energy per kilogram. Both obey E = mc².
Explore electric fields, electromagnetic spectrum, circuit laws, and magnetic force formulas.
Master transverse waves, frequency, wavelength formulas, and wave speed equations ($v = f\lambda$).
Complete physics formula cheat sheet for quantum mechanics, relativity, and nuclear physics.