A proton and an electron have same velocity. Which one has greater de-Broglie wavelength and why?

Explanation

To determine which particle, a proton or an electron, has a greater de-Broglie wavelength when both have the same velocity, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the de-Broglie Wavelength Formula**:
The de-Broglie wavelength (\( \lambda \)) of a particle is given by the formula:
\[
\lambda = \frac{h}{mv}
...