Question

Please explain this:
Force=m*g

Answer 1

Here's your answer! ❤

F = m x g -

It’s a restatement of Newton’s second law for an object in freefall very near a planetary surface.

f is the force applied to a given object (in this case by gravity)

m is the mass of that object

g is the strength of gravity.

Newton’s second law, a more mathematically rigorous elaboration upon his first, says in general that acceleration = force / mass, or a=f/m. This is usually written in the algebraically identical form f=ma for convenience.

This means that the higher the force applied to an object, or the lighter it is, the faster it’ll accelerate.

g is the strength of gravity - in other words, the acceleration of an object in freefall (I.E. an object subject to no forces except gravity) due to the force of gravity. Gravity will apply the same acceleration to any object placed at a particular point in a gravitational field, because the force of gravity will increase proportionally with mass:

F_g = G * M * m / r^2, where F_g is the force of gravity, G is a constant, M is the mass of the planet, m is the mass of the object dropped, and r is the radius from the planet’s center the object is dropped.

Substituting F_g for f in f=ma, and g for a, we get:

G*M*m/r^2 = m * g

G*M/r^2=g

Note that this value of g does not depend on m, the mass of the object being dropped, and in fact is constant for a given altitude above a given planet. We generally approximate g to be perfectly constant for systems very near to a planet’s surface.

We determine g, either by measuring it from f=mg using a force measurement device (like a spring scale) and an object of known mass, or by calculating from the mass and size of the planet. Either way, for Earth, g=9.81 m/s^2, though your teachers’ standards of precision will vary.

Answer 2

The objects relatively close to the Earth, this force is called gravity, and its equation is:F = mg

where

F is the force pulling objects toward the Earth

m is the mass of the object

g is the acceleration due to gravity; this number is a constant for all masses of matter

mg is the product of m times g.