Question

A 4W carbon resistor is colour coaded with Brown, Black, Black and Red respectively. The maximum current which can be passed through this resistor will be

Answer 1

Answer:

I = 0.447 Amps

Explanation:

Let us first decode the value of resistance of the carbon resistor.

According to standard table, a resistor with color coding of Brown, Black , Black and Red can be written as

Red Black Balck Brown ( last last color can only be brown, gold or sliver for tolerance)

Color code for Red is 2, and 0 for black

Hence resistance = 20 ohm ( with 0 tolerance)

P = I^2 x R

4 = I^2 x 20

I = 0.447 Amps