Kirchhoff's rules for resistors in parallel

AI Thread Summary
The discussion focuses on applying Kirchhoff's rules to a circuit with resistors in parallel to determine the currents I1, I2, and I3. The circuit includes an emf of 9 V, an internal resistance of 1.5 ohms, and three resistors with values of 5, 15, and 13.75 ohms. The user calculated I1 as approximately 0.9328 A by combining the resistances and considering the battery's resistance. They expressed difficulty in visualizing the current splits and equivalent resistances due to the lab's unconventional presentation of the problem. A suggestion was made to redraw the circuit using standard schematic symbols for better clarity in analysis.
coleman221
Messages
2
Reaction score
0

Homework Statement



25tko42.jpg


Use Kirchoff's rules to determine I1, I2 and I3 for the following circuit:
Use the following values:ε = emf = 9 V
r = internal resistance = 1.5
R1 = 5
R2 = 15
R3 = 13.75

Homework Equations



The Attempt at a Solution


I found I1 to be .9328 by adding all the resistors together (taking into account that r3 was in parallel to r1 and r2) and adding the resistance of the battery.

I've been trying to use 0=ε-I1r-IR1-IR2
0=ε-I1r-I3R3
I1=I2+I3
I've done similar problems but this is for a lab instead of homework so its written in different a way (and they like to throw in things we haven't learned yet in lecture) so i think I'm having trouble visualizing where the currents are splitting and what parts are equivalent.
 
Physics news on Phys.org
updated to add correct image
 
Why not redraw the circuit in a more conventional way, using the standard schematic symbols? It might help you to see ways to go about analyzing it.
 
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