Air Resistance & Friction · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.
Air Resistance & Friction
Science · Forces & Motion · ages 9-10
Name ______________________ Date ____________
Air resistance, water resistance, and friction all oppose motion.
Circle one: TrueFalse
True or false: Air resistance gets stronger as you go faster.
Circle one: TrueFalse
What force pushes against a skydiver falling through the air?
Static friction
Kinetic friction
Air resistance
Rolling friction
Which force pushes back against you when you swim through water?
Water resistance
Friction
Gravity
What does friction do to a moving object?
Slows it down
Speeds it up
Does not affect it
Makes it float
Why is swimming harder than walking on land?
Water resistance pushes back more than air resistance does
Water pulls you down harder than gravity does
Walking uses more muscles than swimming does
Why does opening a parachute slow a skydiver down?
The parachute makes the skydiver lighter
The parachute blocks gravity
The wide cloth catches more air, increasing air resistance
Look at the chart. Why does the rough rubber pad create more friction than the smooth pad?
A smooth surface always grips better
A rough, bumpy surface grips better than a smooth one
Friction has nothing to do with surface texture
Two skydivers weigh the same. One spreads arms and legs wide while falling. The other curls into a tight ball. Who falls faster?
The one in a tight ball, because a smaller surface means less air resistance
They fall at exactly the same speed
The one spread wide, because a smaller surface means less air resistance
Tom says a bike goes faster over loose gravel than over a paved road because gravel is smoother. Is Tom right?
Yes, gravel is smoother than pavement
The surface makes no difference to the bike's speed
No, gravel is rougher and creates more friction, which slows the bike more
Answer key
For grown-ups. Fold this page away before handing over the rest.
Air Resistance & Friction W1-mt_Y9k86G8BBT-s1
True · That is what makes them alike. Each one pushes against a moving object and slows it down.
True · Air resistance increases with speed. The faster an object moves through air, the more air it has to push out of the way each second.
Air resistance · Air resistance is the force of air pushing against a moving object. A falling skydiver feels air resistance pushing up while gravity pulls down.
Water resistance · Water resistance is the force that pushes back on you as you move through water.
Slows it down · Friction always opposes motion. It acts in the opposite direction, so it slows moving objects down.
Water resistance pushes back more than air resistance does · Water is thicker than air, so it pushes back harder against your body as you move.
The wide cloth catches more air, increasing air resistance · A bigger surface catches more air, so air resistance pushes back harder.
A rough, bumpy surface grips better than a smooth one · Rougher surfaces catch and grip more, creating stronger friction than smooth ones.
The one in a tight ball, because a smaller surface means less air resistance · A tight ball has a smaller surface facing the air, so less air resistance pushes back, letting that skydiver fall faster.
No, gravel is rougher and creates more friction, which slows the bike more · Gravel is bumpy and rough, so it creates more friction than a smooth paved road and slows the bike down more.