Fluids don't have a particular shape (the way a brick does). They acquire the shape of their container by flowing. Let's study how fluids flow, so that we will be better able to understand electrical current.

Here are some things to think about and do as we start the unit on fluids. Each of the following questions requires that you actually do something with a fluid to investigate the question posed, not just talk about what might happen. Please do the following brief investigations.

• A fundamental characterization of a flowing fluid is the flow rate, which is the volume of liquid that is transmitted in a unit of time. We could determine the flow rate of the drinking fountain by measuring the amount of liquid it emits in ten seconds. Or we could measure how long it takes to fill a measuring cup of known volume, and then calculating
      Flow rate = volume produced / time to produce it

  Using your own method, measure the flow rate of the water fountain. Compare it to the flow rate of another faucet turned on full, and just barely turned on (so that there is a tiny stream of water being produced).

• Let's make a siphon. To do this, we need a container mostly full of water, and a piece of tubing from the kit. Fill the tubing with water somehow -- immersing it in the container, for example. Then block one end with a finger, and place the tube so that one end is under water in the container, and the other is outside the container, and no higher than the other end.
  

  Fill the tube	Pull it out, with the end blocked	Unblock the tube

  Now unblock the tube --- and look for a mop! Practice doing this until you are sure you can make it happen every time.

Check the box when you are done: