# Help for Physics lab practical?

Hey all,

I'm trying to prepare for an upcoming Physics lab practical, but I'm having a hard time trying to figure this thing out. I'm not a Physics major, and I really don't have the "eye" that some other people have on what comes to Physics problems. I'm hoping that somebody could help me out a bit, give me tips on how to get started and so on.

Since the given assignment allows the use of book, notes and other materials, I thought I'd ask here if anybody could help me out. Thank you so much for all ideas, tips etc.

Here is what is given:

The "black box" has an on/off switch, a pilot lamp, a ground terminal (the black one in the center), and twelve numbered red terminals. Each of the red terminals corresponds to one and only one of the components or output states listed below. Using the apparatus provided, identify each of the red terminals and write its number on the appropriate line below.

Note 1: If the pilot lamp does not light when the switch is in the "up" position, ask your instructor to replace the battery.

Note 2: All measurements should be taken between a red terminal and the black terminal. Do not connect two red terminals together.

Serial number of unknown:_________________

____________ short circuit (negligible resistance)
____________ 1 Ohm resistance
____________ 1 K Ohm resistance
____________ 1 M Ohm resistance
____________ open circuit (infinite resistance)
____________ 0.47 μ F capacitor
____________ 20 μ F capacitor
____________ diode (semiconductor)
____________ low internal resistance DC voltage source
____________ high internal resistance DC voltage source
____________ square wave AC voltage source
____________ sawtooth (triangle) wave AC voltage source

Before the lab final, you should develop a brief plan or flow chart outlining the equipment you will use and the order you will follow for identifying each of the red terminals. The equipment available will be: oscilloscope, Triplett analog VOM, Keithley digital VOM, function generator, 1 K Ohm resistor, and hookup leads. You may also bring your calculator, textbook, notes, lab reports, and lab manual.

Seems straight forward. As long as the box is in the circuit, you won't really short circuit the battery. You really don't have a quesion here until you have some results.

Nothing about Physics is straight forward to me...

I think I understand that I have to create a series circuit with the "black box," with one hook going in black and another going in red.

Okay, so if one of the tools available for me is 1 K Ohm resistor, I can just hook it between the two lines coming from the red and white connections in the "black box," and find out which one of the red terminals corresponds to the 1 K Ohm resistance. And I guess I need to use the VOM in order to measure the Ohms. Am I correct?

The practical is on tuesday and I'm going insane.

I guess the biggest thing for me to figure out is where do I insert the VOM in the circuit? Anywhere? Like this?

-------"black box"-----function generator-------VOM----------1KOhm resistor--------------(back to "black box")

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