How Do You Calculate the Equivalent Resistance in This Circuit?

[rootX]

Homework Statement

Find equivalent resistance in:
http://img135.imageshack.us/img135/585/62083770ay3.jpg

Homework Equations

The Attempt at a Solution

my
r_eq^-1 = (30+60)^-1+(40+10)^-1
this is wrong.
do i need to include 8 and 4 ohm resistors

 

[stewartcs]

Homework Statement

Find equivalent resistance in:
http://img135.imageshack.us/img135/585/62083770ay3.jpg

Homework Equations

The Attempt at a Solution

my
r_eq^-1 = (30+60)^-1+(40+10)^-1
this is wrong.
do i need to include 8 and 4 ohm resistors

Based on your drawing your equation looks correct. What answer did you get?

You can check your answer against this equation's results:

$$R_{eq} = \frac{R_1 \cdot R_2}{R_1 + R_2}$$

R1 would be 90 since 30 and 60 are in series and R2 would be 50 for the same reason.

CS

 

[Moetasim]

in the calculation?

I would first like to clarify that the concept of equivalent resistance refers to the total resistance in a circuit that is equivalent to the original circuit. This is useful in simplifying complex circuits and understanding the overall behavior of the circuit.

In order to find the equivalent resistance in this circuit, we can use the formula R_eq = R_1 + R_2 + ... + R_n, where R_1, R_2, etc. are the individual resistances in the circuit.

Based on the given circuit, we can see that the 30 ohm and 60 ohm resistors are in parallel, as well as the 40 ohm and 10 ohm resistors. Therefore, we can use the formula for equivalent resistance in parallel circuits, which is R_eq = (R_1 * R_2)/(R_1 + R_2).

Applying this formula, we get an equivalent resistance of 18 ohms for the parallel combination of 30 ohm and 60 ohm resistors, and an equivalent resistance of 8 ohms for the parallel combination of 40 ohm and 10 ohm resistors.

Now, we can see that the 18 ohm and 8 ohm resistors are in series, so we can simply add them together to get a final equivalent resistance of 26 ohms for the entire circuit. Therefore, the answer to the given problem is 26 ohms.

To answer your question, yes, you do need to include the 8 ohm and 4 ohm resistors in the calculation as they are part of the circuit and contribute to the overall resistance.

I hope this explanation helps. Keep up the good work in your studies of circuits and resistances!