Final answer:
The particle with the greatest kinetic energy upon impact with the ground is the fastest particle, as kinetic energy is predominantly influenced by velocity.
Step-by-step explanation:
The question pertains to which particle has the greatest kinetic energy just as it impacts with the ground, given the options A. Heaviest particle, B. Fastest particle, C. Slowest particle, D. Smallest particle. To determine this, we must consider the equation for kinetic energy (KE), which is KE = 1/2 mv2, where m is the mass of the particle and v is its velocity. The kinetic energy of a particle is directly proportional to its mass and, more significantly, to the square of its velocity.
Thus, between particles of equal mass, the one with the greatest velocity will have the highest kinetic energy, and between particles of different masses, it is the velocity that can make a more significant impact on the kinetic energy. Therefore, between a heavy, slow-moving particle and a lighter, fast-moving particle, the fastest particle would have the greatest kinetic energy if its velocity is sufficiently higher compared to that of the heavier particle. Given this understanding, the correct option in the final answer is B. Fastest particle.