**Newtons are the unit of measurement for force.** One newton is the amount of force that is required to accelerate an object that is 1 kilogram in mass at the rate of 1 meter per second.

This unit of measurement was named after physicist and mathematician Sir Isaac Newton, who first understood and explained the nature of gravity, which is the most widely observable force in the universe. Gravity is the force of attraction that two objects exert on each other. It is the force that pulls children back to the ground when they jump up in the air. It is the force that allows satellites, including natural ones like the moon, to stay in orbit around the Earth, and the Earth to stay in orbit around the sun.

The most basic equation for force is: force equals the mass of an object multiplied by its acceleration.

To calculate the force of Earth's gravitational field, acceleration is substituted with the measured acceleration of gravity, which is 9.81 meters per second squared. The human body, on average, has a mass of 40 kilograms; therefore, the human body experiences, on average, 392.4 Newtons of force directed towards the center of the Earth.