Einstein's photoelectric explanation used Planck's E=hf to predict faster electron ejection with higher frequency light
Image: Orren Jack Turner, Public domain, via Wikimedia Commons
Einstein's photoelectric explanation used Planck's E=hf to predict that higher frequency light ejects faster electrons
Einstein's photoelectric explanation used Planck's E=hf to predict faster electron ejection with higher frequency light
Einstein's photoelectric theory posits that light's energy is quantized, not continuous. Planck's equation, E=hf, describes the energy of photons, which is directly proportional to their frequency (f). Higher frequency light means higher energy photons, leading to faster ejection of photoelectrons.
Example
Consider ultraviolet light with a frequency of 1.5×10^15 Hz. Using Planck's equation, E=hf, the energy of each photon is E=6.626×10^-34 Js × 1.5×10^15 Hz = 9.939×10⁻¹9 J. This high energy can eject photoelectrons more quickly compared to lower frequency light.
Remember this
Understanding this relationship helps explain why light intensity doesn't affect electron ejection speed, but frequency does. This insight was crucial for developing modern electronics relying on light detection and electron emission.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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