Question

Consider two particles of different masses. In which of the following situations the heavier of the two particles will have smaller de-Broglie wavelength?

• A. Both have a free fall through the same height
• B. Both moves with the same kinetic energy
• C. Both moves with the same linear momentum
• D. Both move with the same speed

Answer 1

Answer: (A), (B), (D)

Both moves with the same kinetic energy
Both have a free fall through the same height
Both move with the same speed

$\lambda =\frac{h}{p}$, thus, more the momentum the particle smaller is the de-Broglie wavelength. In option A, the speed of the particles is same, thus, the heavier particle will have more momentum. in option B, it can be seen that the heavier particle will have more linear momentum. in option D, they have the same speed , thus, heavier particle will have more linear momentum.