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CBSE Class 12 · 2020 · Modern PhysicsVery Short Answer

A proton and an electron have equal speeds. Find the ratio of the de-Broglie wavelengths associated with them.

Answer: $λ_{p} : λ_{e} = 1 : 1836$

Solution

For equal speeds,

λ = \frac{h}{m v} \Rightarrow λ \propto \frac{1}{m}

.

\frac{λ _{p}}{λ _{e}} = \frac{m _{e}}{m _{p}} = \frac{1}{1836} .

λ_{p} : λ_{e} = 1 : 1836

CBSE Class 12 Board · 2020 · Subjective

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