Page 8 of 14 FirstFirst ... 456789101112 ... LastLast
Results 71 to 80 of 132

Thread: Bledisloe 3 - the sacrifice of the...

      
  1. #71
    Player or Coach

    Soc/Assoc
    None
    Grade
    Level 1
    Join Date
    02 Nov 18
    Posts
    626

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by OB.. View Post
    In what direction was he rotating - forwards or backwards?
    Why was he rotating?

    To be honest, I don't think he was rotating. He'd jumped and leaned slightly back to catch the ball. His left foot was still directly under him, as was his right foot, until he brought it up. Had his foot not made contact with the Aussie lad, he'd have landed just fine. Ian makes it sound like he was on his way to do a back flip of something. This is simply not the case. Also if he hadn't brought his foot up, he'd have landed on both feet, perhaps slightly off balance, but still, would've landed on both feet.

  2. #72

    Referees in England
    Phil E's Avatar

    Soc/Assoc
    Staffordshire and Royal Navy
    Grade
    8
    Join Date
    22 Jan 08
    Posts
    15,233
    Blog Entries
    1

    Default Re: Bledisloe 3 - the sacrifice of the...

    I just don't get Ian's argument.
    If I am on a swing and I kick my legs forward then my legs go up and my body goes back.
    The opposite of what Ian's suggesting.

    Follow my Award Winning blog The Rugby Ref


  3. #73
    Rugby Club Member Flish's Avatar

    Soc/Assoc
    Durham
    Grade
    Level 9
    Join Date
    02 Sep 13
    Posts
    1,310

    Default Re: Bledisloe 3 - the sacrifice of the...

    The cynic in me suggests they're coached to raise the leg to deter anyone from getting too close, although I have no evidence on that one

  4. #74

    Referees in England


    Soc/Assoc
    --
    Grade
    Grassroots
    Join Date
    14 Sep 09
    Posts
    19,259

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by Phil E View Post
    I just don't get Ian's argument.
    If I am on a swing and I kick my legs forward then my legs go up and my body goes back.
    The opposite of what Ian's suggesting.
    don't forget water swirls the other way down the plughole in the southern hemisphere

  5. #75

    Advises in England
    OB..'s Avatar

    Soc/Assoc
    Glos & District
    Grade
    Adviser (grass roots)
    Join Date
    07 Oct 04
    Posts
    22,877

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by crossref View Post
    don't forget water swirls the other way down the plughole in the southern hemisphere
    Despite what you may hear or read, even in some scientific text books, it turns out that the Coriolis force has absolutely no effect on the direction that the water drains from an everyday sink, toilet, shower or bath. It does affect the spin of ocean currents and weather systems such as hurricanes, but on the small scale of a domestic sink the Coriolis force is tiny, and is simply dwarfed by other factors such as the sink shape, differences in temperature or, most likely, residual currents lingering from when the sink was filled with water.
    https://www.theguardian.com/science/...search.science

    Some scientists have managed to create a sink where no other factors apply, but that is far from normal conditions.

    One check is to use your hand to swirl the outflow round the other way and see if it changes back again.
    He trudg’d along unknowing what he sought,
    And whistled as he went, for want of thought.
    The Referee by John Dryden

  6. #76

    Referees in New Zealand
    Ian_Cook's Avatar

    Soc/Assoc
    Retired player and referee
    Grade
    Level 2
    Join Date
    12 Jul 05
    Posts
    13,628

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by Phil E View Post
    I just don't get Ian's argument.
    If I am on a swing and I kick my legs forward then my legs go up and my body goes back.
    The opposite of what Ian's suggesting.
    Watch this girl trampolinist at the Rio Olympics from about 3:00 in the video, and I'll come to your swing example after that



    See how she rotates faster when her legs and/or arms are tucked in and slower when extended out. This doesn't happen because she throws her legs and arms "forwards", it happens because she is extending her limbs "outwards", away from her centre of rotation to slow down and inwards, closer to her centre of rotation to rotate faster.

    What is happening is that she is repositioning some of her mass. That mass has a certain momentum (called "angular momentum" because it is not in a straight line). It maintains that momentum when you move it closer or further away from the centre of rotation. When you move it closer it still has the same momentum, but now it is covering the same distance on a much smaller circle than it was previously - the momentum cannot increase, so the rotation rate increases to conserve the momentum - when the mass is moved outwards, again, the momentum cannot decrease, so the mass has to travel a larger circle, and the rotation rate slows. This called conservation of angular momentum

    I can only have one video per post, so I'll answer the swing question in the next post...
    "You can Google for information, but you can't Google for understanding"
    - Jay Windley

  7. #77

    Referees in New Zealand
    Ian_Cook's Avatar

    Soc/Assoc
    Retired player and referee
    Grade
    Level 2
    Join Date
    12 Jul 05
    Posts
    13,628

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by Phil E View Post
    I just don't get Ian's argument.
    If I am on a swing and I kick my legs forward then my legs go up and my body goes back.
    The opposite of what Ian's suggesting.
    To answer your question, a swing is essentially a pendulum, the rotation is anchored to the point about which you are revolving (NOT rotating), and the principle is similar but not identical. Yes, throwing your legs forward is what you do on a swing, but that is not what causes the swing arc to increase; its the result. Using your arms to pull the chain into a triangle to shorten the distance to the centre of rotation at or near the bottom of the swing arc, and moving your centre of mass away from the centre of rotation when the swing is stopped, is what causes the increase in swing speed.

    I'll let Professor Roger Bowley (University of Nottingham) demonstrate.
    NOTE: That demonstration he does in the classroom before going out and using a playground swing is damn near the exact same one we did in High School physics class, right down to the metal weights and aluminium stand)

    "You can Google for information, but you can't Google for understanding"
    - Jay Windley

  8. #78

    Referees in Australia
    Dickie E's Avatar

    Soc/Assoc
    VRRA
    Grade
    Level 2
    Join Date
    19 Jan 07
    Posts
    13,185

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by OB.. View Post
    https://www.theguardian.com/science/...search.science

    Some scientists have managed to create a sink where no other factors apply, but that is far from normal conditions.

    One check is to use your hand to swirl the outflow round the other way and see if it changes back again.
    https://www.youtube.com/watch?v=pWc9SfwnSxM
    I, for one, like Roman numerals

  9. #79

    Referees in Australia
    Dickie E's Avatar

    Soc/Assoc
    VRRA
    Grade
    Level 2
    Join Date
    19 Jan 07
    Posts
    13,185

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by crossref View Post
    that's my view

    if an egregious act of violence creates a one sided game, then I have no sympathy : don't commit egregious acts of violence.

    but when what is basically an accident (insufficient care / bad technique >> reckless) and a player had no intention of committing foul play, and we RC him anyway (to encourage more care and better technique) ... then fair enough, but it's silly to turn that particular game into a one-sided farce .
    so are you in favour of a 3 card system?
    I, for one, like Roman numerals

  10. #80

    Referees in Australia
    SimonSmith's Avatar

    Soc/Assoc
    Central Australian Rugby Referees
    Grade
    B3
    Join Date
    27 Jan 04
    Posts
    8,780

    Default Re: Bledisloe 3 - the sacrifice of the...

    Quote Originally Posted by Dickie E View Post
    this ^^^.

    The egregious offender is out of the game for it's duration so no different to the black card.

    But the 20 minute rule helps to ensure the game isn't turned into a 1 sided farce which is important.
    To quote Craig Joubert to Drew Mitchell: "I am not responsible for what this does to the game"
    The object of life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane.
    Marcus Aurelius

    Man may do as he will; he may not will what he wills
    Arthur Schopenhauer

    Tullamore Dew, the Afghan Wigs, and many, many strippers - how to get over your ex. How true.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •