Depending on the experimental circumstances, radiation can have either wave-like or particle-like properties. This was very puzzling to scientists in the early 1900s as they could not come up with a theory describing radiation under all circumstances. Eventually, the wave-particle duality was established. It was also proved that matter can emit or absorb energy in specific amounts, or we can say that energy is quantized.
6.2 Wave-Particle Duality
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