How Does Current Flow in a Multi-Loop Circuit with Multiple Voltage Sources?

  • Thread starter Thread starter mbrmbrg
  • Start date Start date
  • Tags Tags
    Circuit Current
AI Thread Summary
In a multi-loop circuit with multiple voltage sources, the current values calculated are i1 at -2.44 A and i2 at -1.33 A, indicating their directions are downward. Energy transfer rates at the batteries show the 4.00 V battery supplying energy at 5.33 W, while the 11.0 V battery supplies energy at 41.6 W. The attempted solution for current i2 involved combining two parallel resistors but led to confusion regarding the relationship between i1 and i2. The user expressed urgency due to an upcoming final exam and sought clarification on the calculations. Understanding the correct approach to analyzing the circuit is crucial for accurate results.
mbrmbrg
Messages
485
Reaction score
2
1. the problem
In Figure 27-69 (see attached), the ideal each resistance is 4.50 and V1 = 11.0 V.


(a) What is the size and direction of current i1? (Take upward to be positive.)
(No Response)[-2.44] A
(b) What is the size and direction of current i2? (Take upward to be positive.)
(No Response)[-1.33] A
(c) At what rate is energy being transferred at the 4.00 V battery and is the battery supplying or absorbing energy?
(No Response)[5.33] W (No Response)[ supplying ]
(d) At what rate is energy being transferred at the 11.0 V battery and is the battery supplying or absorbing energy?
(No Response)[41.6] W (No Response)[ supplying ]


Attempted Solution

Help needed with part b.

for part a: we ignored the right hand part of the cirucuit, and just did the left-most loop. Then we summed the voltages and set them to zero, and got the correct answer.

for part b: We looked at the two right loops and combined them by saying that there are two resistors in parallel which can be replaced by R_{eq}=\frac{1}{R}+\frac{1}{R})^{-1}. Then we tried ignoring the left loop and summing the voltages in the middle loop (with the top right resistor replaced by R_eq) and setting everything equal to zero. That's the wrong answer.
Frankly, I don't understand why i_2\neq i_1.
And the bloody final is tomorrow:cry:
 

Attachments

Physics news on Phys.org
Here's a better diagram, I think, which hopefully will be approved a little more quickly. :wink:

for part b: We looked at the two right loops and combined them by saying that there are two resistors in parallel which can be replaced by

In the new diagram, the two resistors being combined are R3 and R4.
 

Attachments

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top