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Gravity: The Invisible Pull Toward Earth · Gravity is a force that pulls objects down toward the center of the Earth, which is why things fall when dropped. · 5-PS2-1

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Gravity: The Invisible Pull Toward Earth

with Lumi

Lumi the glowing firefly guide hovers in a sunny park, gently releasing a red ball that falls straight down toward the grassy ground below.

Define gravity as an invisible pulling force from Earth.
Predict that dropped objects fall straight down toward the ground.
Compare how gravity pulls both heavy and light objects equally toward the ground.
Identify everyday examples of gravity acting on objects.

Key terms

gravity: an invisible pull from the Earth
force: a push or a pull on something
down: the way toward the middle of Earth
drop: to let go so a thing falls

The Invisible Pull

Gravity is a force that pulls everything toward the Earth. It is invisible, so you cannot see it, but you can always see what it does. When you drop a spoon, it goes straight down to the floor. It never floats up to the ceiling. The huge Earth pulls everything toward its center. That is why letting go of a ball makes it fall down instead of drifting sideways or up into the sky.

Gravity Pulls Everything

Gravity is pulling on you right now. It keeps your feet on the ground and keeps water inside your cup. Without gravity, you would float like an astronaut in space. Gravity pulls heavy things and light things alike. A big rock and a small pebble both get pulled down. If you gently drop a ball, a paper ball, or a block, each one falls down every single time. That is gravity doing its steady job.

Worked examples

You let go of a rubber ball up in the air. Which way does it move?

Gravity is an invisible pull toward the center of the Earth.
That pull always points straight down.
With nothing holding it, the ball follows the pull.

Answer: The ball falls straight down toward the ground.

A friend says gravity only pulls heavy things, not light ones. Is that right?

Gravity pulls on every object near the Earth.
It does not skip light things like paper balls or socks.
So both heavy and light things get pulled down.

Answer: No, gravity pulls all objects down, both heavy and light ones.

Hi friend, I'm Lumi! Let's talk about why things fall. Have you ever dropped a spoon and watched it go straight down to the floor? It never floats up to the ceiling, right? That's because of a force called gravity. A force is just a push or a pull. Gravity is a pull, and it is invisible, so you can't see it, but you can always see what it does. The Earth is huge, and it pulls everything toward its center. That's why when you let go of a ball, it falls down toward the ground instead of sideways or up. Down means toward the middle of the Earth. Gravity is pulling on you right now! It keeps your feet on the ground and keeps water in your cup. Without gravity, you would float in place like an astronaut in space. Gravity pulls on heavy things AND light things — a big rock and a small pebble are both pulled down by gravity. Try this: gently drop one of the objects from our activity — the rubber ball, the crumpled paper ball, or the wooden block — and watch where it goes. Every single time, it falls down. That is gravity doing its job!

Activity

Predict which way each object moves the moment you let go of it.

Practice

Name one light thing and one heavy thing gravity pulls down.

Explain why a dropped spoon falls down and never up to the ceiling.

Common mistakes to avoid

gravity only pulls heavy objectsGravity pulls every object down, even light ones like paper or socks.
dropped things can float upwardDropped things always fall down because gravity pulls toward Earth.

Check your understanding

What does gravity do to objects on Earth?

If you drop a ball, which way will it fall?

A friend says heavy things fall because gravity only pulls heavy objects, not light ones. Is this correct?

Recap

Gravity is an invisible pulling force from the Earth that draws everything toward its center, which we call down. It pulls heavy and light things alike. That is why dropped objects always fall straight down instead of floating up or sideways.

Reflect

What did you drop today, and which way did gravity send it?