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Electric and Resistance, 275, Green Blue, Ked Blue Silver, Yellow, (?), Fig. 5.14, Refer to Fig. 5.14 (ii). Following above procedure, the resistance specification of this resistor, 3 000000, Example 5.26. How will you represent a resistance of 3700 2 t 10% by colour code?, Solution. The value of the carbon resistance = 3700Q ± 10%, The colours of bands corresponding to numbers 3 and 7 are orange and violet respectively., The colour band corresponding to multiplier 10 is red. For 10% tolerance, colour band is silver., Thus the sequence of colour bands on this carbon resistor is orange, violet, red and silver., = 37 x 102 2 ± 10%, PROBLEMS FOR PRACTICE ad biuo, o aidi onodw tuoia s, 1. A voltage of 30 V is applied across a colour coded carbo resistor with first, second, and third rings of blue, black and yellow colours. What is the current flowing through, [0.5 × 10¬ A], the resistor?, 2. The carbon resistor has coloured strips with sequence brown, black, brown and gold., What is the value of the resistor? bsens, upi re/co, A bos de, [U (%S F 00), 3. A carbon resistor is marked in coloured bands in the sequence blue, green, orange, and gold. What is the resistance and tolerance value of the resistor?, [65 × 103 Q; ± 5%], 4. Draw the colour code scheme of 42 k2 + 10% carbon resistance, [yellow, red, orange and silver], 5.21. NON-OHMIC CONDUCTORS, Those conductors which do not obey Ohm's law (I V) are called non-ohmic conductors., e.8., vacuum tubes, transistors, electrolytes, etc. A non-ohmic conductor may have one or more of, the following properties :, (i) The V-I graph is non-linear i.e. VII is variable., (ii) The V-I graph may not pass through the origin as in case of an ohmic conductor., (iit) A non-ohmic conductor may conduct poorly or not at all when the p.d. is reversed,, The non-linear circuit problems are generally solved by graphical methods., Fig. 5.15 illustrates the graphs of non-ohmic conductors. Note that V-I graphs for these, non-ohmic conductors are not a straight line., +1,, Junction, I+, Diode, valve o, Neon, diode, Vogmoa, +Vem, AI-, AI-, Fig. 5.15