LEAFLET: The Physics of Skateboarding -- Doing an Ollie

DID YOU KNOW THAT YOU CAN LEARN PHYSICS

WHILE DOING AN OLLIE?

 

This  is  about  the  science  involved  in doing  an  ollie  while  you’re skateboarding.  It will answer a few of your questions about   how skateboarding works.

It answers the following questions:

What 4 things are required for an ollie?

Which law of motion is involved when you push down – causing   you  and  the board to go up in the air?

 
What force does the grip tape on the board’s top surface provide? 

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WHAT 4 THINGS ARE NEEDED FOR AN OLLIE?     

Sports coach Bobby Mercer recommends that you get started this way:

What You Need

·         -  Flat, paved surface

·         -  3-foot long piece of lumber, at least 6 in. across and 1 in. thick

·         -  Broomstick

·         -  Skateboard

·         -  Helmet

·         -  Elbow and knee pads

What You Need To Do To Prepare

    1.      Place the broomstick on the flat, paved surface.  Place the board (lumber) atop the broom lengthwise, with the broom in the center.

    2.      BALANCE         Stand on the lumber, try to balance over the broom so that neither end of the board touches the ground. 

    3.      SPIN  (rotate)  Once you’ve mastered Step 2, crouch down while balancing.  Push down gently with one foot, and lift up the other foot without taking it off the board. 

The board should rotate around the broom as one end of the board hits the ground  (other end pointing up).

 

 If you can’t do it right away, don’t worry – it’s a tough trick.  Keep practicing.

    4.     PUSH   (hop)    When you get your rotation down (Step 3), it’s time to take the move to the next level.  Crouch down like before, but this time instead of pushing down gently, slam  one  end  of  the  board  down as  hard  as  you  can  with your foot.  If you do it right,  you and the board will fly up off the ground.

    5.      Once you can make the board rotate (Step 3) and hop (Step 4), try it with the skateboard – without the broom.  Make sure you’re wearing your helmet and elbow and knee pads.  Slam the end of the board to the ground and ride the front into the air.

WHAT’S GOING ON?

The ollie is a skateboard move for hopping over objects.  It’s a hard trick, so don’t feel bad if you struggle with it.  Some skateboarders spend months learning how to do it, and some never learn it.

In Brief, the science behind an ollie is:

    
    1)      About shifting your weight  (to exert a force) and

    2)     Obeying Newton’s 3^rd law of motion      
          “For every action there is an equal and opposite reaction."
  
    In Detail:

1) Let’s start with shifting your weight:  when you crouch, you have a lower center of gravity.  That makes it easier to keep your balance.  Simple, huh?

AND THEN WHAT HAPPENS?

Then you slam an end of the board into the floor.  The force you exerted  (to push down) makes the board  rebound (push back up)  off the floor.  This rebound lifts the whole board – and you.

2) That’s because, with Newton’s 3^rd law, the floor supplies an opposite  (upward)   force  equal to your downward slam.

    How fast you hop up depends on your momentum     (a combination of your speed and mass).                     

Did your feet slide around on the piece of lumber?  That should happen less on a skateboard.  Skateboards have grip tape on their topsides,  which  provide  the  friction  needed to hold your feet in place.                      

SO  —  WHAT MAKES FOR A GOOD OLLIE?

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Thank you to Bobby Mercer for presenting  this  so  clearly  and  so approachably  in  his  terrific  book:     The Leaping, Sliding, Sprinting, Riding  Science Book  from  Lark  Books  at Sterling Publishing, 2007.

                Highly recommended!!

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Skateboarding   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 single 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 which I found in: 

    The Leaping, Sliding, Sprinting, Riding Science Book by Bobby Mercer. You may not understand everything in it right away, but for now, use what you do understand

·         
    Conduct an online search of your own

·        
        See what other books and videos your library has

·       
          Share them with your friends, your class, your team, your scout troop

·         
     Read my blog and tell others:   sportscience-kathy.blogspot.com

·      
         See my show on Quincy Access Television, channel 8:  

“Gateway to Science:  Sports & Games”

                                        Thank you!          Kathy Hogan