15 k ohms with a 10% tolerance.
1000 ohms = 1Kohm; silver is the tolerance band of the resistor. Silver signifies plus or minus 10%. The fourth band is always the tolerance band. If there is no tolerance band, the tolerance is plus or minus 20%. A gold band would signify plus or minus 5%.
brown, red, brown, silver = 120 ohms
220 ohms with a 10 percent tolerance. Red is 2 and brown is 1. Brown is in the multiplier band so it is 10 times the value in the first two bands. Silver is in the tolerance band. Gold would have been a %5 tolerance device.
That would be a 200 Ohm resistor, and you didn't mention the tolerance, so I'm guessing you didn't see another band which means the tolerance would be at 20%
The tolerance of a resistor is basically a measure of how close the actual resistance of that particular resistor is to the stated resistance. For example, a "220 ohm" resistor with a tolerance of 10% (silver band) has an actual resistance somewhere between 198 and 242 ohms.
Orange, orange, brown is 330 ohms.
When a resistor has a 4th color band, its color is either gold or silver, so I will assume the color bands are white-white-white-gold. The resistance is 99 GΩ ± 5%.
brown, red, yellow , in case of gold its 5% tolerence, silver 10% tolerence, no color 20% tolence..
On a color coded resistor, there are normally four color bands. The first three represent the value of the resistor and the fourth represents the tolerance of the resistor, i.e. the acceptable variation as a percentage from the stated value. No fourth band allows +/- 20% Silver allows +/- 10% Gold allows +/- 5% Red allows +/- 2% Brown allows +/- 1%
A 0.1 ohm resistor is color coded brown (1) black(0) silver (x 10-2).
Resistors have standard colors for identification of the resistance value. In order, the colors are: black, brown, red, orange, yellow, green, blue, violet, gray, and white. Reading resistors is a very simple procedure if you use the chart and formula below. Hold the resistor with the gold or silver band to the right and read the resistor from the left to the right. http://www.westfloridacomponents.com/reschart.html
the 4 colour resistor colour code is thus: black = 0 brown = 1 red = 2 orange = 3 yellow =4 green = 5 blue = 6 violet = 7 grey = 8 white = 9 the first two numbers are found directly on the table. the third number is not the number, but the number of zeros at the end. therefore the value is yellow = 4, green = 5, and brown equals 1 zero, so the total is 450 ohms. the gold band indicates tolerance. gold is by far the most common, and indicates a tolerance of +/- 5%. therefore the actual value of the resistor could be anywhere between 427.5 and 472.5.