When a force is applied to an object but it doesn’t move, the type of friction acting on it is:

Which of the following would increase the friction between two surfaces?

If the mass of an object is increased, the frictional force between the object and the surface it rests on will:

Which type of friction is generally the weakest?

Why is it easier to slide an object over a smooth surface than over a rough one?

How does adding oil or grease between two metal surfaces affect friction?

When a car skids on a wet road, the friction involved is primarily due to:

Which factor does NOT significantly affect fluid friction?

Which example demonstrates that friction can generate heat?

Which of these is an example of a disadvantage of friction?

Why do athletes wear spiked shoes?

Which of the following will help reduce friction in a machine?

Which of these factors helps a fish move more easily in water?

Friction is useful for which of the following activities?

What is the primary purpose of using lubricants in an engine?

Which factor increases fluid friction as an object moves through water?

Athletes who perform on smooth, polished floors sometimes sprinkle powder on their hands to:

Which statement is incorrect about friction?

Which type of friction is reduced by giving objects a streamlined shape?

In machines, frictional force leads to:

When oil is added to a surface, it:

Heavier objects experience more friction because:

Which surface would allow an object to slide most easily?

In a machine, friction causes:

To initiate motion in an object, the applied force must overcome: