Thursday 21 February 2013

1.27 know and use the principle of moments for a simple system of parallel forces acting in one plane

This criterion means you need to be able to manipulate the moments equation to do questions about forces that are acting on a straight line. It is important to remember that if the straight line is balanced then the clockwise and anti-clockwise moments will be exactly the same. Moment= force x distance.

For example:

C is the pivot of this straight line
The anti-clockwise moment is force x distance= 7n x 5m= 35
As the line is balanced we know that the anti-clockwise moment is also 35
Now we can rearrange the equation to give us the distance in the clockwise moment: distance= moment/force
35/4= 8.75m
So Dm= 8.75m

(nb 5N and DN on diagram are 5m and dm)
Posted by at
Labels: , ,

15 comments:

  1. Kazimali Jaffer5 June 2013 at 00:49

    The question cannot be seen!

    ReplyDelete
  2. aliceinwonderland1528 August 2013 at 06:03

    You really need to work on your spelling Hannah..

    ReplyDelete
    Replies
    1. HannahHelp29 August 2013 at 13:52

      Haha I am sorry! I had been waiting for someone to point that out, I'll proofread this one ;P

      Delete
  3. Test9 March 2014 at 00:23

    This comment has been removed by the author.

    ReplyDelete
    Replies
    1. Test9 March 2014 at 00:29

      This comment has been removed by the author.

      Delete
    2. Test9 March 2014 at 00:30

      This comment has been removed by the author.

      Delete
    3. BOB3 April 2014 at 14:58

      yes

      Delete
    4. Unknown15 April 2014 at 07:31

      I think it would be 1m actually...

      Delete
    5. HannahHelp24 May 2014 at 08:09

      Yeah its one meter :) because he is twice as heavy he must go twice as close.

      Delete
    6. Test24 May 2014 at 20:32

      This comment has been removed by the author.

      Delete
  4. Unknown31 March 2014 at 08:57

    http://astarmathsandphysics.com/igcse-physics-notes/igcse-physics-notes-moments-and-equilibrium.html
    this is the question :)

    ReplyDelete
  5. Unknown3 June 2014 at 07:43

    Hi Hannha do you have any idea on Principle of moments in terms of when you have to work out tension forces in cables etc.

    ReplyDelete
  6. Anonymous17 August 2016 at 02:53

    loll can't see the example?

    ReplyDelete
  7. Unknown6 June 2017 at 01:17

    https://astarmathsandphysics.com/igcse-physics-notes/402-moments-and-equilibrium.html

    This is the link which works

    ReplyDelete

Subscribe to: Post Comments (Atom)