How_To_Be_Good_At_Math

Mass and weight

Mass and weight

We often use the word weight when we mean mass but

they’re not actually the same. Weight is how hard the force

of gravity attracts an object and is measured in a special

unit called Newtons (N).

Even though your weight would be different,

your mass would stay the same. This is

because your mass is the amount of matter you

are made up of, so it doesn’t change.

If you were to travel around the Universe,

your weight would change depending on

where you were. This is because the gravity that

acts on you is different in different places.

Your mass and weight are almost the same

everywhere on Earth. This astronaut’s weight

on Earth is 1200 N. Her mass is 120 kg.

On the Moon, the astronaut

weighs about one-sixth of

what she weighs on Earth

because the Moon’s gravity is

one-sixth of Earth’s gravity.

In outer space, there is no gravity, so

even though our astronaut has no

weight, she still has the same mass as she

would have on Earth.

The astronaut would weigh more than

twice as much on Jupiter compared to

Earth because Jupiter’s gravity is much

stronger than Earth’s. She would feel very

heavy, but her mass would remain the same.

ON EARTH

MASS 120 KG

WEIGHT 1200 N

IN SPACE

MASS 120 KG

WEIGHT 0 N

ON THE MOON

MASS 120 KG

WEIGHT 200 N

ON JUPITER

MASS 120 KG

WEIGHT 2700 N

Mass is the amount of

matter something is

made up of. Weight is

the amount of gravity

acting on something.

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