Beginning of Essay
A typical bomb has four major parts: the outer case, devices such as fins to stabilize it in flight, one or more fuzes, and a mechanism for arming the fuze or preparing it to explode. The case may be made of metal, glass, plastic, or concrete, and its shape and si ....

Middle of Essay
.... explodes underwater. The cases of hand grenades are lightweight because troops carry these small bombs and throw them at the enemy. Most time bombs are built according to the circumstances and concealed next to their target. They may consist of explosives and a timer in a cardboard box or some other inconspicuous casing. Without fins to stabilize them in flight, bombs would be almost impossible to aim. The fins transform a bomb from an unstable nonspinning projectile into a stable spinning weapon that travels through the air like a bullet. There are two types of bomb fuzes. An impact fuze detonates a bomb when the projectile strikes its target, and a ....