A proton moving in a uniform magnetic field with v1= 1.23 ×10^6 ı^m/s experiences force F1= 1.88 ×10^−16k^N. A second proton with v2= 2.36 ×10^6ȷ^m/s experiences F2=− 3.60 ×10^−16k^N in the same field. Required:
a. What is the magnitude of B?
b. What is the direction of B?

A. they hold atoms  together with a molecule.its a force that exist between molecules. hope this .

  concave means having an outline or surface that curves inward like the interior of a circle or sphere. so the mirror curves inward.

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.