Broomball is played on a hockey rink like
the one pictured below.
(Image courtesy of http://www.polarnet.ca/kugluktuk/rechall/)
When one examines the hockey rink closer one
discovers that the game is simply played on ice. Most people
know that ice is slippery, but fewer know that the kinetic
coefficient of friction between ice and ice .03. This simply
means that the play surface is going to be slippery.
We know this because of Newton's first law.
Simply put, the aspect of this law relevant to us states,
a body in motion will remain in motion unless acted upon by
outside forces. The major outside forces that usually allow
us to stop is friction. On ice the friction coefficient is
greatly reduced to what it is on a sidewalk. Therefore stopping
is made much more difficult. This adds an element to the game
play that is missing from most other sports. Understanding
this concept can make one a better broomball player. However
there are broomball shoes, which are discussed in the equipment
section of this site.
To better understand the concept of ones movement
on the ice the free body diagram of a moving person in relation
to the ice is below. (Note: F sub you incorporates
friction)
However it is also important to point out
that because the ice is surrounded by a "wall" of
wood and plastic panels, a player can use these to stop, go,
or change direction quickly. The ball can also be played off
of this barrier.
With the power of physics on can predict where
the ball will land. We know that in elastic collisions momentum
and kinetic energy is conserved. If we can guesstimate the
angle of attack of the ball in relation to the wall we can
figure out where it will land on the ice. Approximately anyway
because we don't know the acceleration of the ball.
Some people find sliding to be a good solution
to stopping without falling on your back. This works by spreading
your force over a larger area thus increasing the surface
area contact of your body in relation to the ice. However,
sliding can take you out of the play because the ice makes
it harder to get started running again, especially when you
are laying down. This is because the static friction coefficient
between ice and ice is 0.1.
Let us recall the concept of throwing your
keys away from you while standing on a frictionless surface.
One can't walk on a frictionless surface, so in order to move
we must add a new element. If we throw our keys one way our
mass will slide the opposite direction because there isn't
friction.
This is perhaps the most important concept
related to the playing surface in broomball. When one swings
to hit the ball if his/her center of gravity is too high (they
are standing fully erect) they are more likely to fall then
if they lower their center of gravity by kneeling or bending
over. The momentum of the stick (given by P=mv) is like throwing
keys. Therefore, due to Newton's third law, there will be
an equal yet opposite reaction, you falling.
As previously stated, the playing surface
add a unique element to the game of broomball. If one understands
the physics behind the playing surface and how to use it,
one's game will be elevated to a new level.
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