Understanding Friction

When things slide, like a sled going down a hill, they slow down when they reach the bottom. Why? Because the ground helps stop them! This is called friction. Friction happens when two things rub together, like the sled and the ground. It helps stop the sled so it doesn't keep going forever!

Are you ready to answer some questions?

What is friction?

• When two things rub together

• When things fly in the air

• When things glow in the dark

What helps a sled stop at the bottom of the hill?

• The wind

• Friction

• The sun

Why is friction important?

• It makes things stop or slow down

• It makes things go faster

• It makes things disappear

High friction occurs when two surfaces resist motion because they are rough or have a large contact area. It makes objects harder to move.

Choose two surfaces where friction is high.

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Low friction happens when two surfaces slide or roll past each other easily, with little resistance.

Choose two surfaces where friction is low.

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