This is a blog of the 4th grade class in la Farigola de Vallcarca School in Barcelona. This year we are doing “Aula de Ciències” in English.
In this blog we want to show you the experiments we do in our Science Lab. Science is fun!

dilluns, 2 de novembre de 2009

Building bridges

MATERIALS: 2 thick books 1 piece of card 1 lid from a jar paper clips and small objects such as rubbers, pencil sharpeners... INSTRUCTIONS: Put two thick books about 15cm apart. Lay the piece of card on the books and place the lid on top. Add paper clips to the lid; the bridge starts to sag; count the clips before the bridge collapses. Make a second bridge, but now bend the piece of card into an arch between the books. Place the lid on top of the arch. Add paper clips; count them before the bridge collapses. If not, add small objects. WHY: The first bridge collapses before because it is flat and it has to take all the weight. In the second bridge the weight is passed along the card into the books. The weight is shared and the bridge can support more weight. OUR EXPLANATIONS: The books are heavy and stop the piece of card go down. (Carlos) If the bridge is flat, the edges go up; in the arch, the card can't go up and bend. (Roger) The books press the card and it is more difficult. (Lluc) The mountains (books) hold the bridge. (David) WHAT DO YOU THINK ABOUT? WRITE YOUR COMMENTS!

6 comentaris:

  1. This experiment is useful beacause the engineers can build more resistant bridges .It's very funny! beacause we learn a lot.
    Dana, Anna and Inés.

  2. In the laboratory our group put 59 clips and the flat bridge sag. Later we made an arch with the card and we put 300 clips and it didn't sag.We added 6 pencil sharpeners and 5 rubbers.
    This experiment is useful.


  3. Laboratory in English is very useful, because you learn both, English and Science. I liked this experiment very much. Inés.

  4. 1- We put 37 paper clips on a flat piece of card and it goes down.
    2- On the piece of card we put 300 paper clips, 7 rubbers and 7 pencil sharpeners.
    This experiment is very boring (Lluc) and very cool (Carlos).
    Lluc and Carlos

  5. Roger P. R. and Marc S. R.12 de novembre de 2009 a les 12:26

    In our group we can put 37 clips on the flat bridge and on the arch bridge we can put 300 clips, 7 rubbers and 7 pencil sharpeners. This experiment is very cool.
    Roger and Marc.

  6. This experiment is very boring.