Question: Do we need to calculate the resistivity of wires if using massive of them? For example, if we are using a big and thickness wire/ 1000 jumper wires/ long wires in a installation.
The question that came from the processes of my homework: I saw someone use resistors on the FSR sensors, but I tried to remove resistors that connected to the FSR because I was thinking it might affect the function and it still works. So do we need to always connect resistors to the sensors?

For the reading 2 of Norman,  Chapter 1, “Attractive Things Work Better”
I do strongly and sympathetic agree with his argument about an attractive design (with useful functions) for objects are more letting the things work better.

some notes:  V = I* R
I = V / R
R = V / I
connection in series:     R total = R1 + R2 +....+Rn
connection in parallel:   1 / R total = 1 / R1 + 1 / R2 +...+ 1 / Rn

Making an application with switch and led.
I am always liking to use FSR pressure sensors. I want to try lighting a led with FSR sensor that I have.
Firstly, I tried to just connect the Arduino and led just for lighting it up, then I followed the video to write the code into the Arduino for controlling the led.  This is the code that wrote into the Uno. Then I prepared for a FSR switch in a circuit!
Here are the materials that I used in that application:
· Arduino uno
· Force sensitive resistor
· LED
· 220 Ohm resistor Connecting them into a circuit. // for FSR led
int ledPin = 7;
int sensorPin = A0;
int value;

void setup(){

pinMode(ledPin, OUTPUT);
Serial.begin(9600);
}
void loop(){