Question
What is the resistance between A and B in the figure given below?
✓
Answer
The three resistance of 20 ohm, 10 ohm and 20 ohm on the extreme right side are in series. So, the resultant of these three resistance = 20 + 20 + 10 = 50 ohms. This 50 ohms is in parallel with 30 ohms. so resultant of these two will be
$\frac{1}{\text{R}}=\frac{1}{30}+\frac{1}{50}$
$\frac{1}{\text{R}}=\frac{80}{1500}$
R = 18.75 ohms Now, the resistance 10 ohms, 18.75 ohms and 10 ohms are in series. Therefore, resultant resistance = 18.75 + 10 + 10 = 38.75 ohms.Need a full question paper?
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