The Wheatstone bridge shown in the figure below, gets balanced when the carbon resistor used as R 1 has the colour code (orange, red, brown). The resistors R 2 and R 4 are 80 Ω and 40 Ω , respectively. Assuming that the colour code for the carbon resistors gives their accurate values, the colour code for the carbon resistor, used as R 3 , would be

Step-by-step solution

Colour band A and B indicate the first two significant figures of resistance in 'ohm', while the C band gives the decimal multiplier i.e., the number of zeros that follows the two significant figures A and B . The last band D indicates the tolerance in percentage about the indicated value or in other word, it represents the percentage accuracy of the indicated value. For R 1 , the given colour of the rings of a carbon resistor are orange, red, brown then, the value of resistance is R 1 = 32 × 10 1 Cond