We have direct daily experience with two of these forces: gravity and electromagnetism. Consider, for example, the everyday sight of a person sitting on a chair. The force holding the person on the chair is gravitational, and that gravitational force balances with material forces that “push up” to keep the individual in place. These forces are the direct result of electromagnetic forces on the nano-scale. On a larger stage, gravity holds the celestial bodies in their orbits, while we see the universe by the electromagnetic radiation (light, for example) with which it is filled. The electromagnetic force also makes possible the advanced technology that forms much of the basis for our civilization. Televisions, computers, smartphones, microwave ovens, and even the humble light bulb are made possible by control of electromagnetism. The average physics major will spend more time understanding and applying the concept of electromagnetic force than he or she will spend studying any other type of force.
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