Final answer:
Beta particles penetrate matter more deeply than alpha particles due to their smaller size, requiring denser materials like aluminum for protection, whereas alpha particles can be blocked by paper or skin.
Step-by-step explanation:
When comparing the penetration abilities of alpha particles and beta particles, beta particles can penetrate matter more deeply. This is because beta particles are much smaller and lighter than alpha particles, which makes them less ionizing but gives them a greater capability to penetrate into matter. Alpha particles, being larger and carrying more mass, can be easily stopped by thin barriers such as paper or a human hand. In contrast, beta particles require denser material like a quarter-inch thick sheet of aluminum to be stopped.
For personal protection against alpha particles, a barrier as simple as a sheet of paper, clothing, or skin can effectively block them since they are easily halted by a small amount of matter. However, for beta particles, which are more penetrating than alpha particles, a heavier barrier such as wood or aluminum is necessary to provide effective shielding.