Invisible Forces Check Up

In the watermelon video, the last rubber band caused the watermelon to burst because...

• it was stronger than the other rubber bands.
• it was thicker than the other rubber bands.
• it was the last rubber band in the bag.
• it created a force that was greater than the force of the watermelon rind.

The suspension bridge was a good design for the Golden Gate Bridge in San Francisco because...

• ships had to pass underneath the bridge.
• it has lots of pillars underneath it to support it.
• the distance the bridge had to cross was not very long.
• the water under the bridge was very shallow.

Why are pillar and arch bridges stronger than a simple board bridge?

• They are bigger.
• Board bridges are usually made by kids and the other ones are made by grownups.
• Board bridges can sag in the middle, but the other bridges have more support.
• They are not made of wood.

Push, pull or both?
Pressing a button

• Push
• Pull
• Both

Push, pull or both?
Throwing a ball

• Push
• Pull
• Both

Push, pull or both?
Towing a person on a raft

• Push
• Pull
• Both

Push, pull or both?
Stomping your foot

• Push
• Pull
• Both

Push, pull or both?
Yanking your sister's hair

• Push
• Pull
• Both