Friday, February 19, 2016

COLLISION! What's That?

COLLISION
Elastic v. Inelastic

Two things collide with each other!

On a scale of 1 to 10, how elastic or inelastic is the collision?

1            2            3              4            5             6              7              8             9            10
ELASTIC                                                                                                INELASTIC
(has a lot of "give")                                                                            (not enough "give")
 You can find out just what this means when you have an
EGG TOSS -- OR WATER BALLOON TOSS

Use an easily breakable item – that's why we use an egg or a water balloon.
In a contest like this, after each round, you take a giant step back, so there is more and more distance involved. The distance adds to the amount of force each time you throw.

How elastic or inelastic a collision?                         It depends on:
USE AN EGG or WATER BALLOON                     WHERE IT LANDS AND HOW IT LANDS
Using the above scale:

                      1                                             on sand or grass or a pillow

                      3                                             in your hands, and keep the arms moving

                      5                                            in your hands, stop all of a sudden

                      7                                             right on you!

                     10                                             on hard ground
                                                                                            

You can find out, too, with pitching and catching:
PITCHER / PITCHING MACHINE

How elastic or inelastic a collision?                           It depends on:
USING DIFFERENT TYPES OF BALLS                HOW YOU PROTECT YOURSELF

cloth ball                                       1                               bare hands

rubber ball                                     3                               bare hands

softball                                          5                               catchers mitt

baseball                                         7                               catchers mitt

ball used in shotput                       10                             2 catchers mitts ??!

SUMMARY: The force is d-i-f-f-u-s-e-d, meaning you s-p-r-e-a-d  o-u-t the force.

This  way  there  is  a  more  elastic  collision,  resulting  in  less  damage.

So, wearing a helmet helps protect you when doing activities such as bicycling or skateboarding. Why? If you fall and hit your head, 
it spreads the force, first, throughout the lining --- protecting YOU. 

How? Less force to your head!

 

Proposal for a Legislative Resolution

RESOLUTION
WHEREAS...
Children play,

WHEREAS...
Children acquire language,

WHEREAS...
Children's bodies understand the feeling of various forces that they experience while at play – whether in the playground or on the playing field – or in any other daily activity,

WHEREAS...
Massachusetts has long been a leader in education and has a vast sports infrastructure,

THEREFORE, BE IT RESOLVED THAT:

...Children be helped to learn basic scientific principles in the playground and through the sports and games that they enjoy.

...Their working vocabulary be expanded to include words such as Friction, Gravity, Energy, Momentum, Axis of rotation, Inertia, Trajectory, Potential energy and Kinetic energy, Torque, Angular momentum, Lift, Air resistance, and Elastic collision, for example.

...STEM / STEAM be amended to STEAMS:
Science – Technology – Engineering – Arts – Mathematics – Sports

...The following specific recommendations be developed, modeling for other states how this can be done:

  • sports camps
  • preschools
  • after-school programs
  • professional development for teachers and coaches
  • methods courses in education programs
  • high school and college level Physics of Sports courses, with the gymnasium as the applied physics lab
  • sports stadiums via activities and Jumbotron

...The Commonwealth of Massachusetts take the lead in developing this approach to science education – one that is natural, logical, and fun (and long overdue).

...Form an institute dedicated to teaching people how to do this.


Tuesday, February 2, 2016

Leaflet: Science of Skiing

DID YOU KNOW THAT
YOU CAN LEARN PHYSICS
WHILE SKIING ?

This is about the science involved in downhill skiing.

Why is skiing on packed powder better than skiing right after a snowfall?

What things can I do to be sure of a nice smooth ride down the slope?

What kind of simple machine is a ski slope?

What is aerodynamics? And what does it have to do with skiing?


GATEWAY TO SCIENCE:
SPORTS AND GAMES

                                     http://sportsciencekathy.blogspot.com


WHAT KIND OF THINGS CAN I LOOK FOR WHEN I HIT THE SLOPES?

First of all, that ski slope is actually a machine – what we call a simple machine. It's an inclined plane, just like a ramp. It makes work easier. And if you had to ski down a hill that wasn't smooth, skiing would be harder. Wouldn't it?

After a fresh snowfall, the hill is not so smooth until the snow be-comes packed. As you're standing at the top of the hill getting ready to push off, your position there gives you a lot of potential energy: the higher you are, the more you have.

Crouching down and pushing off -- kinetic energy of motion combined with the pull of gravity -- along with a smooth surface and smooth skis -- means YOU will have an exciting ride down the hill!

WHAT KIND OF FORCES ARE INVOLVED IN DOWNHILL SKIING?

Energy: Potential energy at the top of the ski slop -- which changes to kinetic energy when you're in motion

Gravity: A force that pulls you to the earth, so it aids downhill motion

Friction: Occurs when 2 surfaces meet. A lot of friction (rough, bumpy) makes motion harder; and a little friction (smoother) makes motion easier.

Aerodynamics: Wearing smooth clothes and crouching help you to reduce friction between yourself and the air less drag. Your shape is more like a bird or a plane (aerodynamic).

NOTE
Center of mass, or center of gravity:
Bending your knees helps you find your center of balance.

Skiing...

is just one of endless ways to gain an understanding of physics and geometry. I hope this leaflet introduces you to seeing things you never saw before – or wondered about but just didn't know where to start.

Physics and geometry come into play in every activity and event going on around us.
Knowing how things work can add to your performance and to your fun. So give it a try. How?

  • Start with the information here
  • You may not understand every- thing in it right away, but for now, use what you do understand
  • Do an online search of your own
  • See what books or videos your library has
  • Share them with friends, your class, your team, your scout troop
  • Read my blog and tell others:
    sportscience-kathy.blogspot.com
                              Thank you! Kathy Hogan
                                                        Gateway to Science: Sports and Games


                                                 
                                                                                               Picture: Univ. of Utah

REFERENCES:
Skiing: It's All About Friction
Marcia Howell, Univ. of Utah

NOTE: Univ. of Utah is a good resource for sport science in general.


NBCLearn.com and the National Science Foundation did videos at the 2010 Winter Olympics on sport science, narrated by Lester Holt. See YouTube.


          Sports and games are the gateway to science,
                                 and YOU hold the key!