Name: _________________________


Activity:  Yesterday we explored the current in circuits, today we want you to do the same, but with a little more direction.  Make sure you follow the rules from yesterday:

        1.  Draw diagrams for every circuit you try.
        2.  Use a switch.
        3.  Set the meter to its highest current setting first, then if the value you get is too low, you may turn the setting down.
        4.  Always connect the meter so the current will flow through it, and then through the rest of the circuit -- otherwise you won't be measuring the current in the circuit at all.
        5.  Always make sure NOT to connect the meter directly to the battery, and do make sure that there is something else in the circuit other than the battery and the meter.
        6.  If you are unsure if your setup is safe, ask the teacher to check it before you connect anything.


1.  Using two of the black light bulbs, make a series circuit as shown below.





    a. Make a prediction:  If the current through position (a) were 40 mA, what do you think the current through positions (b) and (c) would be?

    b. Test your prediction, and record your measurements on the above diagram.


    c.  Why do you think you got the result you did?

2.  Redraw the circuit diagram below. This time you will use two pink bulbs.

    a.  Make a prediction – what will the current be at each of the 3 positions? (You can just guess if it will be equal to before, higher than before, or lower than before).

    b.  Test your prediction, record your measurements on your above circuit diagram.

3. Explain.
   
   
   

3.  Redraw the circuit again. This time you will use a pink bulb in the first position, and a black bulb in the second. (label the bulbs appropriately)

    a.  Make a prediction – what will the current be at each of the 3 positions? (You can guess the values relative to the previous examples).





    b.  Test your prediction, record your measurements on the above circuit diagram.

3. Explain.
   
   
   
   
   
   

4.  Now make a parallel circuit like the one below, using black bulbs.







    a.  Make predictions -- what will the current be at each of the locations, if the current at (a) is 40mA?






    b.  Test and label the above diagram





    c.  Explain







5.  What does the circuit arrangement in number 4 do to the total current?  Why?

6. Repeat number 4, but now use one pink bulb and one black bulb. What changed?

7.   Construct other circuits that you want to test, draw diagrams for each of them, and measure the current in multiple locations in each circuit.

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