Friction Flashcards
What is static friction?
Static friction is the force that resists the initiation of sliding motion between two surfaces in contact.
How do static and dynamic friction differ?
Static friction acts when there is no relative motion between the surfaces, while dynamic friction acts when there is relative motion.
What is dynamic friction?
Dynamic (kinetic) friction is the force that opposes the motion of two surfaces sliding past each other.
What is the coefficient of limiting friction?
The coefficient of limiting friction is the ratio of the maximum static frictional force to the normal force between two surfaces.
How can the coefficient of limiting friction be determined?
It can be determined by measuring the maximum force required to start moving an object and dividing it by the normal force.
What are the advantages of friction?
- It allows us to walk or drive without slipping.
- It enables the braking of vehicles.
- It is essential in the functioning of various machines.
What are the disadvantages of friction?
- It causes wear and tear on materials.
- It leads to energy loss in the form of heat.
- It can reduce the efficiency of machines.
How can friction be reduced?
Friction can be reduced by:
- Using lubricants.
- Polishing surfaces.
- Using wheels or rollers.
- Streamlining shapes to reduce air or fluid resistance.
What is viscosity?
Viscosity is a measure of a fluid’s resistance to flow.
What is terminal velocity?
Terminal velocity is the constant speed that a freely falling object eventually reaches when the resistance of the medium prevents further acceleration.
How do viscosity and terminal velocity relate?
Higher viscosity in a fluid increases the resistance to motion, which can lower the terminal velocity of an object moving through it.
What does Stoke’s law describe?
Stoke’s law describes the force of viscosity on a sphere moving through a fluid.
How is Stoke’s law applied?
It is used to calculate the terminal velocity of small spherical objects falling through a viscous fluid, considering factors like radius, fluid viscosity, and density differences.
