Guest

How do I find equivalent resistance??................................

How do I find equivalent resistance??................................

Question Image
Grade:12

2 Answers

Shwet prakash
20 Points
6 years ago
You can find TOTAL RESISTANCE in a Parallel circuit with the following formula: 1/Rt = 1/R1 + 1/R2 + 1/R3 + ... " Before we get into the calculations, remember what we said at the start of this section: "The total resistance of a parallel circuit is NOT equal to the sum of the resistors (like in a series circuit).
Sanju
106 Points
6 years ago
There are 12 resistors in the given diagram. If ‘R’ is the resistance of each resistor, then the equivalent resistance between the point A and B is 4R/5.
Here we use vertical symmetry to find the equivalent resistance b/w A &. It bit difficult to explain it without diagram as I can’t insert images. So I will try to explain it through words.  The tip of the second triangle on the upper half (with tip downward) can be detached from the common meeting point & redrawn in such a way that the same current passes through the 2 sides making it a series combination. The equivalent of this series combination is in parallel connection to the resistor on the base of the second triangle. Applying the equation for parallel connection, the equivalent resistance comes out to be 2R/3. Likewise, the equivalent resistance of the second triangle on the lower half (with tip upward) is also 2R/3. Now we have 2 resistors on the left and right sides of this 2R/3 resistance on the upper & lower half. Since they are in series, its equivalent resistance is 8R/3. Also we have two resistors in series between the line joining A and B. Equivalent resistance of these 2 resistors is 2R as they are also in series. Now the connection gets simplified as: 8R/3 || 2R || 8R/3 (The symbol || means ‘parallel to’). Or in other words, we have 3 resistor combination in parallel connection-8R/3 (upper part), 2R (middle part) and 8R/3(lower part). Now find the equivalent resistance of these 3. It will give you equivalent resistance as 4R/5.

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free