11. The Electromotive force ( EMF ) of a concentration cell with transference includes the liquid junction potential. 12. Electromagnetic induction produces an electromotive force within a conductor which is exposed to time varying magnetic fields. 13. Dissimilar metals in contact produce what is known also as a contact electromotive force or Galvani potential. 14. This generates an electromotive force , and thus some of the light energy is converted into electric energy. 15. This analogy became so widespread that sources of voltage are still today referred to as electromotive force . 16. The electromotive force generated by a time-varying magnetic field is often referred to as " transformer emf ". 17. The strength of the pile is expressed in terms of its electromotive force , or emf, given in volts. 18. In the armature, an electromotive force is created by the relative motion of the armature and the field. 19. The induced electromotive force is caused by a change in the magnetic flux linking the coils of an inductor. 20. There he prepared a thesis on electromotive force which gained him a doctor's degree in Paris the following year.