ADMICRO

Read the passage below carefully and choose the correct answer a, b, c, or d.

DOWN-TO-EARTH IDEAS

If a big apple and a small one drop from an identical height at the same instant, which one will reach the ground first? Neither! Without air resistance, a large apple will reach the ground no sooner than a small one. Many people find this hard to believe since it seems to contradict “common sense”.

A great Italian mathematician and physicist named Galileo first proved that, without friction, a heavy object and a light one released from the same height will reach the ground at the same instant.

He had begun to suspect that the common notion about heavier objects falling faster than lighter ones was false when he experimented with pendulum. He found that a heavy pendulum swung no faster than a lighter one. Galileo went on to experiment with balls rolling down a sloping plank and proved that heavy balls reached the bottom no faster than light balls.

Galileo’s investigation with the dynamics of motion revealed another important law of physics: that, apart from air resistance, bodies accelerate constantly as they fall. In a vacuum (where there is no air resistance) a heavy object does not fall faster than a light one; the rate of acceleration (32 feet per second) is the same for all objects. Thus any object travels faster at the end of its fall than at the beginning.

It may be inferred from the article that__________ .

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