Which ball has greater acceleration as both drop toward the ground?

The correct answer, which states that both balls have equal acceleration, is based on one of the fundamental principles of physics related to the motion of objects under the influence of gravity. According to Galileo's experiments and Newton's laws of motion, in the absence of air resistance, all objects fall at the same rate regardless of their mass. This means that both balls will experience the same gravitational acceleration, which on Earth is approximately 9.81 m/s².

This equality in acceleration is fundamentally tied to the concept that the force of gravity acts uniformly on all objects, leading them to accelerate downwards at the same rate. While their masses might be different, this does not affect the rate at which they fall. Hence, the assertion that both balls have equal acceleration is supported by the principles of gravitational acceleration in a vacuum or ideal conditions without any significant air resistance acting on them.