Classical Mechanics and Projectile Moves

When an object (stone, spear, arrow or bullet) is thrown, hurled or shot in the air, the object is a PROJECTILE (“Projectile”). The study of projectile is important because it must be realized that they are very much part of man’s daily life then and now. Whether man likes it or not, he encounters and uses projectile in his everyday life. Our hunting ancestors threw stones and spears on animals to kill them for their food. In today’s sports, balls follow projectile motion such as when a basketball player shoots the ball into the hoop, a golfer or a baseball player hitting the ball, a tennis player lobbing the ball, a javelin thrower, a discus thrower or a shot putter trying to throw their objects as far as they can (Sears, Zemansky and Young 54). In warfare, catapults and arrows in medieval times were the deadly weapons while today, guns, mortars, rockets and missiles have replaced those ancient weapons of war (“Field Artillery and Mortars”, “Ballistics”). However, the way to effectively use these weapons has not changed. They are to be launched into projectile motion to hit the target. The path followed by a projectile is called its trajectory. Projectiles follow a curved trajectory or curved path that is a PARABOLA. (Sears, Zemansky and Young 54, Briggs 491). It is actually easy to observe projectile motion when we use a light material as the projectile. For example, crumple a sheet of bond paper into a small ball. On a standing position, throw the paper ball straight horizontally. Observe that as the ball moves, it curves downward. Even if you try to throw it harder, it will still follow a curved downward path but will land farther. So, the harder you throw the object straight horizontally, the farther it will land. The distance where the object lands measured horizontally from the point you threw it to the point where it landed is called the RANGE of the projectile. The range of the projectile can be increased by

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