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What is friction and its types?

‘Friction‘ is a force that resists motion of sliding or rolling of one object moving relative to another. It is a result of the electromagnetic attraction between the charged particles of two touching surfaces.   Types of Friction Static Friction : It is defined as the frictional force that acts between the surfaces when they are at rest with respect to each other. The magnitude of the static force is equal in the opposite direction when a small amount of force is applied. When the force increases, at some point maximum static friction is reached. Rolling friction : It is the force that resists motion when an object rolls on a surface. Technically it’s not friction; its ‘rolling resistance’ since when a body rolls perfectly upon a surface, on paper, there is no sliding friction between that object and surface. Sliding friction : It is the frictional force between two surfaces that are rubbing against each other. It’s a very easy and common concept. It’s hard to find a perfectl...
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Define Acids, Bases and Salts.


Acids, Bases and Salts : A substance that tastes sour in water, turns blue litmus red, and neutralises bases is known as an acid. If a substance’s aqueous solution tastes bitter, turns red litmus blue, or neutralises acids, it’s called a base. Salt is a neutral material that has no effect on litmus in aqueous solution.

Arrhenius theory

  • Acids : when dissolved in water, dissociates to give H+ (aq) or H3O+ ion.
  • Bases : when dissolved in water, dissociates to give OH− ion.

Bronsted Lowry theory

  • A Bronsted acid is an H+ (aq) ion donor.
  • A Bronsted base is an H+ (aq) ion acceptor.




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What is friction and its types?

‘Friction‘ is a force that resists motion of sliding or rolling of one object moving relative to another. It is a result of the electromagnetic attraction between the charged particles of two touching surfaces.   Types of Friction Static Friction : It is defined as the frictional force that acts between the surfaces when they are at rest with respect to each other. The magnitude of the static force is equal in the opposite direction when a small amount of force is applied. When the force increases, at some point maximum static friction is reached. Rolling friction : It is the force that resists motion when an object rolls on a surface. Technically it’s not friction; its ‘rolling resistance’ since when a body rolls perfectly upon a surface, on paper, there is no sliding friction between that object and surface. Sliding friction : It is the frictional force between two surfaces that are rubbing against each other. It’s a very easy and common concept. It’s hard to find a perfectl...
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Read more