The other day during my Phsyics Practical exam, we were supposed to carry out two simple experiments. The first was to tie a steel ball to a string of rubber, pull the ball downwards, and see how high the ball would bounce up to. Simple enough. The second experiment required us to connect a d.c. circuit to resistors and measure the potential difference across it using a voltmeter. We were to carry out the experiment first with one resistor, then with two, three, four, five, and six, measuring the potential diference across the resistors each time we changed the number of resistors used.
Maybe some of you reading this may not know what a resistor, a voltmeter, or even a d.c. circuit is. Not to worry. The main point should be easy enough for you to understand.
Anyway, I connected the voltmeter and the resistors to the batteries provided with some wires. After the connection was complete, I tried the voltmeter but it gave no readings. I tried adjusting the wires into position but it still didn't work.
Sensing that I needed help, my lab tutor came to my assistance.
"My voltmeter always zero one." (Yes, as every typical Malaysian, I use Manglish in everyday conversations.)
"Check your connections."
"I check d. Everything also okay."
My lab tutor checked my circuit. He picked up a wire with a loose end.
I forgot to complete the circuit by connecting the wire to the negative terminal of the battery.
"See, what is this?"
Hey, at least I don't ask if my sandwich is tuna or chicken, right?