Problem

Problem

A proton, a deuteron and an alpha particle are accelerated through potentials of VV, 2V2V and 4V4V respectively. Their velocity will bear a ratio
Intuitive explanation

The key insight is that kinetic energy gained equals the work done by the electric field: qVacc=12mv2qV_{\text{acc}} = \frac{1}{2}mv^2. Since each particle has charge proportional to its proton number and mass proportional to its mass number, you can rearrange to find v∝qmv \propto \sqrt{\frac{q}{m}} for each particle. Calculate this ratio for a proton, deuteron, and alpha particle using their actual charges and masses, then compare.

Intuitive explanation

The key insight is that kinetic energy gained equals the work done by the electric field: qVacc=12mv2qV_{\text{acc}} = \frac{1}{2}mv^2. Since each particle has charge proportional to its proton number and mass proportional to its mass number, you can rearrange to find v∝qmv \propto \sqrt{\frac{q}{m}} for each particle. Calculate this ratio for a proton, deuteron, and alpha particle using their actual charges and masses, then compare.

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