7. Friction, Inclines, Systems

Which type of friction resists the movement of an object that is already in motion?

A car with mass $m$ is moving at constant velocity on a horizontal road. If the normal force between the tires and the road is $N$ and the frictional force opposing the motion is $F_k$, what is the coefficient of kinetic friction between the car’s tires and the road?

Which type of friction resists the motion of an object that is already moving along a surface?

While driving on a slippery highway, which action is most effective in reducing the risk of skidding due to kinetic friction between the tires and the road ($f\_k$)?

Which of the following is an example of static friction?

Which of the following best describes the effect of kinetic friction ($f\_k$) on a moving object?

Which of the following best describes the difference between $\mathrm{static} \mathrm{friction}$ and $\mathrm{kinetic} \mathrm{friction}$?

When a ball rolls across a rough horizontal surface and gradually slows down, what force is primarily responsible for the ball's deceleration?

Which of the following lists correctly identifies the main types of friction encountered in physics?

A mug of mass $m$ rests on a horizontal table. If a horizontal force is applied and the mug moves at constant velocity, what is the magnitude of the frictional force exerted on the mug?

For a sliding object moving across a horizontal surface, how does the kinetic friction force ($f{k}_{}$) depend on the object's speed ($v$)?

Which statement best explains why the coefficient of kinetic friction between two steel surfaces is relatively high because of steel's ductile nature?$\mu k_{}$

A block A with mass $m$ is pushed across a horizontal tabletop with a constant velocity by a horizontal force of magnitude $F$. What is the coefficient of kinetic friction between block A and the tabletop?

Three identical crates are pushed across different surfaces: crate A on ice, crate B on wood, and crate C on concrete. If the normal force is the same for all, rank the crates from least to greatest kinetic frictional force acting on them.