Write an expression for the work done by friction as the block slides from A to B. Your answer should be in terms of m, h, vB, and g (the acceleration due to gravity).

Complete Question

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The expression is  

Explanation:

Generally the work energy theorem is mathematically represented as

     

Here   is the potential  energy at A which is mathematically represented as

       

And   is the kinetic energy at B which is mathematically represented as

       

So

     

=>  

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.