Force
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In physics, a force is an action that can cause an object to change its velocity or its shape, or to resist other forces, or to cause changes of pressure in a fluid. In mechanics, force makes ideas li
Aristotle famously described a force as anything that causes an object to undergo "unnatural motion"
Sir Isaac Newton in 1689. His Principia presented his three laws of motion in geometrical language, whereas modern physics uses differential calculus and vectors.
Galileo Galilei was the first to point out the inherent contradictions contained in Aristotle's description of forces.
Images of a freely falling basketball taken with a stroboscope at 20 flashes per second. The distance units on the right are multiples of about 12 millimeters. The basketball starts at rest. At the time of the first flash (distance zero) it is released, after which the number of units fallen is equal to the square of the number of flashes.
Potential energy
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In physics, potential energy is the energy of an object or system due to the body's position relative to other objects, or the configuration of its particles. The energy is equal to the work done agai
In the case of a bow and arrow, when the archer does work on the bow, drawing the string back, some of the chemical energy of the archer's body is transformed into elastic potential energy in the bent limb of the bow. When the string is released, the force between the string and the arrow does work on the arrow. The potential energy in the bow limbs is transformed into the kinetic energy of the arrow as it takes flight.
A trebuchet uses the gravitational potential energy of the counterweight to throw projectiles over two hundred meters
Springs are used for storing elastic potential energy
Archery is one of humankind's oldest applications of elastic potential energy