Green = 5, brown = 1, black = 0, silver = 0.01, then
Resistance value = 510 × 0.01=5.1Ω
II. Expression method of capacitor capacity
The basic unit of capacitor capacity is "farad" (f), and 1/1000000 (one millionth) of 1 farad is 1 micro method( μ F) , 1/1000000 of 1 micro method is 1pf (1 micro method, or 1 skin method). The relationship between them is the carry relationship of millions (or the 6th power of 10).
Our commonly used capacitors are:
1. Dielectric capacitance: mostly at 1 μ Above F, directly expressed in numbers. For example: 4.7 μ F 、 100 μ F 、 220 μ F, etc. The two poles of this capacitor are positive and negative, and the long leg is the positive pole.
2. Ceramic chip capacitance: mostly at 1 μ Below F, directly expressed in numbers. For example, 10, 22, 0.047, 0.1, etc. pay attention to the unit here. If expressed as an integer, the unit defaults to PF; Where decimal is used, the unit is defaulted μ F 。 As in the above example, they are 10p, 22P and 0.047 respectively μ F 、 220 μ F, etc.
Now another expression similar to the color ring resistance is popular internationally (the unit is pf by default):
For example, "473", i.e. 47000 pf=0.047 μ F
"103" means 10000 pf=0.01 μ F, etc,
The first and second digits of "XXX" are significant digits, and the third digit represents the number of 0 added later. This representation is already quite common.