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.
Gravity
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In physics, gravity, also known as gravitation or a gravitational interaction, is a fundamental interaction, which may be described as the force that draws material objects towards each other.
Force
…three of Newton's laws of motion. Types of forces often encountered in classical mechanics include elastic, frictional, contact or "normal" forces, and gravitational. The rotational version of force is torque, which produces changes in the rotational speed of an object. In an extended body, each part applies forces…
The shapes of two massive galaxies in this image evolved under the effects of gravity.
The Leaning Tower of Pisa, where according to legend Galileo performed an experiment about the speed of falling objects
English physicist and mathematician, Sir Isaac Newton (1642–1727)