Bridges
Describe a board bridge.
A bridge where a board is just laying flat across the 2 ends.
If you wanted to go down a slide faster, what are some things you could do? Why would those things help?
Make the slide more slippery, wear slippery clothes, or ride on slippery material. All those things would make the friction force less strong, so the pull of gravity would bring you down the slide faster.
Describe an arch bridge.
A bridge with a curve (arch) to help support weight.
Sandpaper sliders don't slide very fast because....
sandpaper creates a lot of friction.
Describe a pillar bridge.
A bridge with strong posts (pillars) under it to help make it strong.
Why is it hard to win a tug-a-war against a group of teachers?
Teachers have a lot of friction.
Why was a suspension bridge a good design for the Golden Gate Bridge in San Francisco?
Ships had to pass underneath the bridge.
Magnets attract...
objects that contain iron.
Why do hoppers hop off the table?
The stretched rubber band is pulling at the cardboard when it is laying flat. When you let go, the rubber band pulls the sides together and makes it push off the table.
The last rubber band caused the watermelon to burst because...
it created a force that was greater than the force of the watermelon rind.
Why are pillar and arch bridges stronger than board bridges?
The force of people and cars pushes a bridge down. The pillars and arches push up from below to balance the downward push force from the people and cars. The board bridge does not have anything to push from underneath to make it stronger.
Are paper clips magnets?
Paper clips are not magnets, but they do stick to magnets.
What is one way we could have changed the hopper experiment to make it work better?
Used a different rubber band or stronger cardboard.