There are following three factors that affect an object's (an athlete, a hammer, a shot or a javelin) flight :
1. Angle of projection : Any object when projected at different angles (as shown in covers different distances. When it is
projected or released at the angle of 30°, making a parabolic path, it covers less distance i.e., AB. When it is projected at the angle of 60° it covers a distance i.e., AC and when it is released at the angle of 45°, making a parabolic path it covers the maximum distance i.e., AD. Here it is ‘ supposed that the initial velocity in all the cases is same. So, the distance covered by an object (implement such as shot, hammer or javelin etc.) depends on the angle of release of projectile. Scientifically, it can be said that the angle of 45° is the best angle for achieving maximum distance. If an object is projected at the angle of 90° it does not cover any distance but falls on the same spot from where it is projected.
2. Projection height relevant to the landing surface : If the height of the projection and the landing surface is equal then release
the object at the angle of 45s. If the level of the landing surface is more than the height of projection, increase the angle of projection, means above than 45°. If the level of landing surface is less than the height of projection decrease the angle of projection, means less than 45°. So, the horizontal distance of an object depends on the relevancy of projection height and landing surface.
3. Initial velocity : The distance covered by an object depends on the initial velocity of the projectile. If the initial velocity is more, the object covers maximum distance. On the other hand, if initial velocity is less, the object covers less distance. (1 each)