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How is the SI unit of force connected to kilograms, metres, and seconds?

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Title page of Isaac Newton's Philosophiae Naturalis Principia Mathematica, 1687, featuring large Latin text and publication details in a bordered layout. — Newton’s laws of motion The title page of Isaac Newton's *Philosophiae Naturalis Principia Mathematica* (1687; *Mathematical Principles of Natural Philosophy*), the work in which the physicist introduced his three laws of motion.

In the International System of Units (SI), the newton (N) is the standard unit of force. It is defined as the amount of force required to provide a mass of one kilogram with an acceleration of one metre per second squared.123

This relationship is derived from Newton’s second law of motion, which is expressed by the formula:

$F = m \times a$

In this equation, force ( $F$ ) is the product of mass ( $m$ ) and acceleration ( $a$ ). When using SI base units, the unit of force is expressed as:

$1 N = 1 kg \cdot {m/s}^{2}$

Essentially, one newton is the force that causes a one-kilogram mass to increase its velocity by one metre per second during every second the force is applied.45