why cannot an athlete stop instantaneously when he reaches the end after arace?
Answers
Answer:
There is a great concept in physics which is also referred to as Newton’s First Law which explains how inertia works. Basically, a body in motion will stay in motion and an immobile object will not move unless there is a force acting on the object.
Picture the athlete as an object in motion. This object currently has a lot of kinetic energy due to its motion and needs to get rid of this energy in order to come to a full stop. The conventional way to get rid of energy is to apply some form of braking force, such as friction. In the case of runners, it involves using your legs to brake by using antagonistic muscles to apply a force that is opposite to the direction in which you are going. Thus, we typically rely on our muscles to stop. Now, your muscles can only handle a given mount of force without getting injured. Any force greater than this may lead to injury. As such, applying a force that is too great in order to stop may lead to injury.
Now, if we put all of this ramble into a usable piece of information, we get the following:
A force produced by an athlete’s muscles is required in order to get rid of his/her kinetic energy and come to a full stop. The muscles can only handle a certain amount of force without injury. This means that an athlete coming to an abrupt stop will require a great amount of force to do so. This high amount of force will be generated by eccentrically loading* the muscles, which could lead to an injury due to the tension produced. As such, people don’t stop abruptly because it may lead to injury.
*Eccentric loading: occurs when the muscle lengthens while producing a force. This force is often used to slow down a movement, such as putting a box down gently. Excessive loading leads to injury.