Concept:A body in free fall accelerates constantly downward due to gravity, meaning its velocity continuously increases over time.
Formula:$$ \lambda = \frac{h}{mv} $$
Solution:- As the falling object accelerates (velocity \( v \) increases every instant), the denominator in the de Broglie equation grows larger.
- Because wavelength \( \lambda \) is inversely proportional to velocity \( v \), a continuously increasing velocity yields a continuously shrinking wavelength.
- Therefore, the wavelength continuously decreases.
Why other options are incorrect:Increasing wavelength would require the object to be slowing down. Remaining constant would require the object to fall at a terminal (constant) velocity, which contradicts "freely falling".
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