The Physics of Sports
Starting August 5, the Olympics in Rio will gather more
than 10,000 athletes from 206 countries competing in
42 disciplines. Most of the athletes have put in years of
intense, focused physical and psychological training.
For those who will be watching them, or who play sports
themselves, It has been created a virtual special issue
called The Physics of Sports.
Understanding the physics of motion can affect all
areas of sports, from helping athletes move faster, to
preventing injuries, planning more efficient trainings,
and developing aerodynamic equipment and clothing.
Physics and sports are intimately connected. This is
because every sport’s discipline depends on the ability
of an athlete to exercise a force, and a force is one of
the key elements of Newton’s laws of motion and other
elementary physics concepts.
Work and energy in pole
vaulting
Work and energy are
among the most important
concepts of physics. Both,
work and energy, play an
important role in sports.
In physics, work is defined
as the result of a force
moving an object a certain
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THE CLAPPER 2018 - 2019
distance. Thus, force and work are directly proportional
to each other. In addition, the concepts of work and
energy are closely related. Hence, work transfers energy
from one place to another or one form to another.
During a pole vaulting performed by athletes, different
types of energy are involved. First, the athletes transform
chemical energy into kinetic energy of their body while
running. Part of this kinetic energy becomes elastic
potential energy, as observed by the deformation of the
pole; the rest of energy becomes gravitational potential
energy, which again it is transformed into kinetic energy
while the athletes fall away from the bar.
Angular momentum in skating
In physics, if a system is isolated from its surroundings,
that is, if no external forces acting on it, there are three
conserved quantities (which means they maintain the
same level or energy or transform into other types
of energy): energy, linear momentum and angular
momentum. In classical mechanics, conservation of
linear momentum (the product of the mass and velocity
of an object) is implied by Newton's laws.
Angular momentum – also known as rotational
momentum – is the quantity of rotational motion a body
has. It is the product of the moment of inertia (i.e., the
product of the mass of the object and the square of its
perpendicular distance from the axis of rotation) and
rotational velocity.
Conservation of angular momentum is another
important concept. For example, consider a figure skater
who turns on the tip of her
skates. In the absence of
external forces, the angular
momentum is almost
constant. When a figure
skater draws her arms and
a leg inward, she reduces
the distance between the
axis of rotation and some
of her mass, therefore