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has magnitude only. directed toward the center of the Earth or other gravity
well.

Mass is commonly measured Weight is commonly measured in Newtons.
in kilograms and grams.

Mass doesn’t change Weight varies according to location.
according to location.

The mass may be measured Weight is measured using a spring balance.
using an ordinary balance.

What is Weightlessness?

Have you ever been in an elevator? Noticed how you feel like your weight is been
reduced while the elevator goes down? That is because the weight you feel is the
perceived weight or “effective weight”, this is the equal and opposite force the floor
exerts on you due to your weight. Now if we remove the floor and let you fall freely there
is nothing to exert a force on you and hence you will feel weightless even though there
is acceleration due to gravity and mass. This is because the effective weight is equal to
zero. Now let’s come back to our elevator when the elevator is going down it is actually
moving in the direction of the gravity, hence reducing net acceleration due to gravity,
thereby reducing your weight.

The same happens with astronauts in the international space station, as the space
stations are orbiting the earth it is falling towards the earth indefinitely and everything in
it is falling including the astronauts so the astronauts experience weightlessness and
can float freely around. In all these scenarios the most important thing we have to