Resistors

Resistors

With resistors we learned how to read the color code of four band and five band resistors.

For example

A four bands resistor with brown, black, brown and brown it means

Brown      Black         Brown      Brown

1                0                10              1% tolerance

The resistance of this resistor is

10 X 10 Ohm +/- 1%  = 100 Ohm +/- 1%

A five bands resistor with brown, black, brown, brown and brown it means

Brown      Black         Brown      Brown      Brown

1                0                1                10              1% tolerance

101 X 10 Ohm +/- 1%  = 1010 Ohm +/- 1% = 1.01 kOhm +/- 1%

In series cct total resistance is

R_total = R₁ + R₂ +…+R_n

In parallel cct total resistance is

1/R_total = 1/R₁ + 1/R₂ + …+ 1/R_n

When connect resistors in series they add up to give a greater total resistance. In parallel cct the total resistance of the cct is decreasing as more resistors are connected in parallel.