Final answer:
In football, spearing refers to the act of striking a runner with the crown of the helmet, which is prohibited. Players are advised to tackle with their feet on the ground, utilizing momentum, work, and energy for safer and more effective plays. A small force can impart the same momentum as a large force when applied over a longer period of time.
Step-by-step explanation:
In football, spearing refers to b) Striking a runner with the crown of the helmet. This dangerous technique involves a player using the top part of their helmet to make forceful contact with an opponent, which is prohibited because it increases the risk of head and neck injuries, including concussions, for both the tackler and the player being tackled. Coaches recommend that players block, hit, and tackle with their feet on the ground, utilizing proper techniques to ensure safety and improve effectiveness.
When football players keep their feet on the ground, they can make better use of the concepts of momentum, work, and energy. A player on the ground can achieve a stable position to generate maximum force and maintain balance, leading to a more controlled and powerful tackle. Additionally, maintaining contact with the ground allows players to leverage their body weight efficiently, improving the effectiveness of their blocks and hits.
An understanding of momentum is also crucial in football. Momentum is the product of an object's mass and its velocity. A football player can impart the same momentum to an opponent by using a small force over a longer period of time as a large force applied quickly. This is why driving into a tackle with controlled force and full-body contact, instead of a rapid, focused impact like spearing, is more effective and safe.