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# In which of the following situations the heavier of the two particles has smaller de Broglie wavelength? The two particles.

A. move with the same speed

B. move with the same linear momentum

C. move with the same kinetic energy

D. have fallen through the same height.

Answer :

de Broglie wavelength is λ==

where λ is wavelength, h is Planck's constant, m is the mass of a particle, moving at a velocity v and k is the momentum.

∴ According to above relation, If particle velocity, mass, momentum or its kinetic energy increases, de Broglie wavelength decreases.

Same momentum particles have same de Broglie wavelength.

If velocity is constant heavier mass particle will have smaller de Broglie wavelength. Similarly it applies for kinetic energy.

If particle falls from same height, velocity will be same irrespective of its mass.

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