Answer:
• Friction is a force that occurs when two surfaces slide past
one another.
• The force of friction opposes the motion of an object,
causing moving objects to lose energy and slow down.
• When objects move through a fluid, such as air or water, the
fluid exerts a frictional force on the moving object. The
frictional force from a fluid is called a drag force.
• Friction examples: tires skidding to a stop on a road,
sandpaper rubbing against wood, air pushing against the
nose of an airplane
• Friction drag force causes objects to slow down as they move through a
fluid, such as air or water.
• Drag force depends primarily on the following variables:
– Cross‐sectional area of an object moving through the fluid
– Speed of moving object
– Density of the fluid
– Drag coefficient (determined by experiments; related to the shape of
the object)
• Drag force is especially dependent on the speed of an object. As an
object’s speed increases, the drag force from the fluid increases
exponentially.
• For example, when you drive at high speeds, the frictional force of air on
the car increases and fuel economy decreases
Hope this helps, have a nice day/night! :D
