Which factor can decrease the kinetic energy of an object? Increase in speed
Decrease in speed
Increase in temperature
Decrease in volume

The magnets are probably damaged or there not strong enough to attached to the refrigerator

Pe = 1/2k(x)^2  and .05n/m = .05x10^-9m = x 

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.