  The electron and the proton have a negative electrostatic charge and a positive electrostatic charge respectively. Each charge-and the force associated with that unit of charge-is constant-and equal.(The electron and proton have equal, but oppositely polarized, electrostatic charges.) But there is more. The electron and the proton have a negative electrostatic charge and a positive electrostatic charge respectively. Each charge-and the force associated with that unit of charge-is constant-and equal.
The start of life for the tank did not bode well. The first model came off the factory floor on September 8th 1915. On September 10th, its track came off. The same happened on September 19th when government officials were watching.
Tanks in World War I were developed separately and simultaneously by Great Britain and France as a means to break the deadlock of trench warfare on the Western Front. Their first use in combat was by the British Army in September 1916 during the Battle of the Somme. The name tank was adopted by the British during the early stages of their development, as a security measure to conceal their purpose (see etymology).