What is the pressure exerted by a boy

weighing 80kg on the ground when he stands

on his feet whose area is 200cm2 ?

A. 80 pa

B. 1600 pa

C. 40,000 pa

D. 400 pa

Protons have a positive charge and, collectively, give an element its atomic number.

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.