a shape that reduces the amount of air friction over a moving object, such as a vehicle. This helps it move faster.

• AERODINAMIC SHAPE

• GRAVITY

• FRICTION

AIR

• is matter: it has mass and volume

• abundant gases are nitrogen and oxygen

• abundant gases are helium and oxygen

• it doesn't have mass.

a vehicle that can fly, like an aeroplane

• AIRCRAFT

• AIRFORCE

• FRICTION

a thin part of a helicopter that rotates.

• BLADE

• WING

• AIRCRAFT

the ability that something has to float

• BUOYANCY

• DENSITY

• GRAVITY

Objects float when their density is ____ than the density of the water.

• LOWER

• HIGHER

• EQUAL

push or a pull

• CONTACT FORCE

• NONCONTAC FORCE

• GRAVITY

DENSITY

• a specific property of matter

• a general property of matter

• It is calculated by dividing mass by volume

• It is calculated by dividing volumne by mass

a motor that uses energy to make machines move

• ENGINE

• FORCE

• WING

Objects ___ when their density is lower than the density of the water.

• FLOAT

• SINK

• GO AWAY