The atomic number is 5. The atomic number gives the number of protons. Protons which have a positive charge are balanced by an equal number of electrons in a neutral atom. Boron number 5 has five protons and therefore as a neutral atom also has five electrons. Boron atomic number 5 has five electrons in its ground state. Commonly Boron will lose 3 electrons leaving 2 electrons in its most common ionic form.
During the course of a continuous isometric contraction of given strength, the electrical activity progressively increases. This is due to recruitment of motor units taking place to compensate the decrease in force of contraction occurring in the fatigued muscle fibres.