Question

The equivalent resistance between points $a$ and $f$ of the network shown in figure:

A) $24\Omega$
B) $110\Omega$
C) $140\Omega$
D) $200\Omega$

Answer 1

In these kinds of situations the first thing important is to notice the given problem statement. Specially this is a trick question as per the standards. Here there is no interconnection and the question is just asking for simply the two points. Therefore we just need to find the series equivalent for the given resistances.

Complete step by step solution:

Here there are $3$ resistances given between $a$ and $f$ , so we just have to find the series equivalent for the given resistances:
${R_{eq}} = {R_1} + {R_2} + {R_3} \\\ {R_{eq}} = (10 + 50 + 80)\Omega \\\ {R_{eq}} = 140\Omega \\\$

Note: Most important thing here is to notice the structure of the diagram as it is the initial and generally most careless state. Apart from that it is necessary to observe what process is straight and easy to find the equivalent resistance and then we can execute the formulas.