One basic law of nature says that all actions must take place using the least amount of energy. To violate the law, one must pay a penalty that usually involves adding more energy to the system from an outside source. Hold an object in the air. The object has potential energy. A person holding the object in the air must contribute additional energy to continue maintaining the object at its potential-energy level. Release the object and the potential energy changes to dynamic energy. Upon hitting the floor, the dynamic energy causes deformation of the floor and heat. Now the floor must contribute the force to maintain the position of the object. The scientific explanation sounds complex, but examples in the real world are easy to understand.
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