Lab: Electronics and using a Multimeter

Notes

For using the multimeter, the lab says to “Turn the function knob to the Diode/Continuity Function” before the description of the symbols around the knob, so if you haven’t used a multimeter before, it’s not clear what that means in relation to the symbols. I did figure it out eventually, though!
Voltage goes from 0.98 to 0 when the button is pushed

Circuit with a button connected in series with a LED, with the button off

Circuit with a button connected in series with a LED, with the button on

At first, when adding a second light in series, neither were lighting up. I tested each of the components to make sure they all worked individually, which they did. I finally figured it out when I tried substituting in lights of different colors; it turned out that putting two red leds in series let both of them light up faintly, but if one of them was white, neither of them lit up. This is probably because the white requires more voltage than red, and the combination of red and white means neither is getting the voltage needed to turn on.

White and red LED units connected in series with at 3.3 V (note how even with the button pushed down, they don’t light up)

Two red LED units connected in series with at 3.3 V

Adding voltages for lights in series:
- Measured power to ground: 3.38
- Added together: 0.06 (resistor) + 1.64 (first red LED) + 1.64 (second red LED) = 3.34
- Added together (with white LED): 0.00 (resister) + 0.99 (red LED) + 1.78 (white LED) = 2.77
Trying to measure amperage: the circuit connects, but the reading is just 00.0 at any setting

Measuring amperage with lights connected in parallel

Dimming an LED with a potentiometer

Is there a way to measure voltage between power and ground rows on the breadboard when the probe tips are too big to fit through the holes? Do you just need smaller probe tips?
This lab talks about measuring amperage, but not really what it is — is it the same thing as current?