A roller coaster containing four cars is accelerating at 15 m/s2 before it comes to an abrupt stop at the end of the ride. The mass of one car is 200 kg. How much force was exerted on the roller coaster to bring it to a stop? A - 60N
B - 800N
C - 3000N
D - 12000N

The car would move to the right with 150 n of force. the 150 n of force from friction and air resistance slows the car from moving to the right with 300 n of force.

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.