> > > > > > a 12 n horizontal force f pushes a block weighing 5.0 n against a vertical wall. the coefficient of static friction between the wall and the block is 0.60, and the coefficient of kinetic friction is 0.40. assume that the block is not moving initially. (a) will the block move? (b) in unit-vector notation, what is the force on the block from the wall?

Friction is donated by F

f=μR

12N force is used to push block into the wall 
R=12N

μ=0.6
Putting values we get
f=0.6×12

To maintain the static condition of block the friction must be equal to weight.So, if 
f=mg
Then the block does not move

Scientific classification

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.