Page 50 - G5.1_M1-5
P. 50
DO NOT EDIT--Changes must be made through “File info”
CorrectionKey=TX-B;NL-B
myNotes
Center
of mass
A regular wheelchair tips over fairly easily. The
vertical dotted black line shows that the center
of mass is directly over the tipping point.
Why They’re Better is why no one built a light wheelchair for
athletes sooner. It seems this invention
6 The reasons why a lightweight had to wait for Marilyn Hamilton: not only
wheelchair is better for athletes than a
did she understand the need, she also had
traditional wheelchair are pretty easy to the connection to hang-gliding technology
understand. In fact, Sir Isaac Newton that turned a dream into a reality.
figured out the exact math formulas to
8 The lightness of the Quickie was the
explain this stuff back in 1687, but here biggest innovation. But Hamilton and her
are the basics:
friends didn’t stop there. They worked
• to move something heavy, you have hard to figure out what else an athlete
to push harder; would need. In the end, the Quickie was
• given the same push, something made more stable by giving it a lower
light will go faster than something center of mass and a wider wheelbase
heavy; and than a traditional wheelchair. An object
• it’s easier to slow down a lighter will tip over when the center of mass is
object than a heavier one. directly over the point of tipping. The
diagram above shows that with a
7 So, it’s obvious that a lighter lower center of mass and a
wheelchair will let an athlete move
faster, stop faster, and change direction wider wheelbase, the sports
easily. The only thing that isn’t obvious wheelchair must be
pushed to a much greater
angle before it tips.
traditional Something that is traditional has been
made or done in a certain way for a very long time.
50
