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Guilherme Mazui

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What is the Difference Between Static and Sliding Friction?

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The main difference between static and sliding friction lies in the motion of the objects they affect. Here are the key differences between the two types of friction:

Static Friction:

  1. Acts on objects at rest, preventing them from moving.
  2. Requires a force to be overcome before the object can start moving.
  3. In some cases, the maximum static friction force can be less than the force required to move the object.
  4. Examples include a car parked on an incline or a box on a flat surface that does not move when pushed.

Sliding Friction:

  1. Acts on objects that are already in motion, opposing their sliding motion.
  2. Requires a force to be applied continuously to maintain the motion of the object.
  3. Typically weaker than static friction, making it easier to move a sliding object.
  4. Examples include a block sliding across a floor or a hockey puck sliding on ice.

In summary, static friction prevents objects from moving, while sliding friction opposes the motion of objects that are already sliding. Static friction is generally stronger than sliding friction, making it more difficult to initiate motion in objects at rest.

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  • What is the Difference Between Static and Sliding Friction?
  • Comparative Table: Static vs Sliding Friction

    • Comparative Table: Static vs Sliding Friction

    Here is a table comparing static friction and sliding friction:

    Property Static Friction Sliding Friction
    Definition Static friction is the force that acts between two surfaces that are at rest with respect to each other, resisting their motion when a force is applied. Sliding friction is the force that acts between two objects that are sliding against each other, resisting their relative motion.
    Examples - Skiing against the snow
    - A table lamp resting on the table    		 - Sliding of a block across the floor
    - Two cards sliding against each other in a deck
    Coefficient The coefficient of static friction is denoted as µs. The coefficient of sliding friction is denoted as µk.
    Formula Mathematically, static friction is defined as: $$Fs = µs \eta$$, where $$Fs$$ is the static frictional force, $$µs$$ is the coefficient of static friction, and $$\eta$$ is the normal force. Mathematically, sliding (or kinetic) friction is defined as: $$Fk = µk \eta$$, where $$Fk$$ is the kinetic frictional force, $$µk$$ is the coefficient of kinetic friction, and $$\eta$$ is the normal force.
    Force Magnitude Static friction is generally stronger than sliding friction. Sliding friction is weaker than static friction but still resist the motion of two objects sliding against each other.

    In summary, static friction acts between two surfaces at rest with respect to each other, while sliding friction acts between two objects that are sliding against each other. Static friction is generally stronger than sliding friction, and their magnitudes can be calculated using their respective coefficients and the normal force acting on the objects.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.