Physics - Weight
Weight (W) is a force that acts on any object near the earth's surface at
all times - it is inescapable! More generally, it acts whenever an object
is in a gravitational field - a field that could be due to any massive
object such as a moon, planet, sun or asteroid.
It always acts towards the centre of the massive object - in our case this
is down, towards the centre of the earth. The weight of a mass (m) near any
other massive object (such as a planet) is given by the formula:
The weight  force does not depend on any other factors like speed or
direction of motion.
The weight force is considered to act from the centre of gravity  of
the object, which, for relatively small objects, is in the same position as
the centre of mass.  The weight vector always points down.
All objects have weight. The weight arrow is drawn with its origin at
the object's centre of mass.
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