lab1
2a)
I used red LED so in order to limit current to 30mA, I needed X ohm resistance.
2b)
R is the minimum resistance. (V = IR) if resistance go down, current go up and LED might fail.
2c)
0-10kohm
I measured the resistance range of potentiometer with multimeter.
3a)
The resistor and LED are in series and hence the order of the components between the power and ground doesn't matter.
4a)
V = IR
(9-1.85) = 0.03 x R
R = 283ohm
my button circuit:
http://www.youtube.com/watch?v=ZDLYwnFoUtE
my potentiometer circuit with 9V battery:
http://www.youtube.com/watch?v=Zfft_tROtyE