Calculating I4 in Combination Circuit

Thread Starter

aeln269

Joined Oct 18, 2020
30
Screen Shot 2020-10-29 at 12.58.04 AM.png
Ive tried two methods. The one in the textbook using I4=(R3/R3+R4)I2 and an online method from this video
. Ive followed both to a T and still it marks me wrong. Ive been working on this problem for nearly 2 hours now and cant get it. My initial answer was 0.53 using the method from the book and using the video I got 0.067. What am I doing wrong? Im losing my mind.
 

Thread Starter

aeln269

Joined Oct 18, 2020
30
thank you, ill try to in the future but im not too great with computers. how do I put the photos all into one post?
 

ericgibbs

Joined Jan 29, 2010
11,122
hi,
You say you have 230mA [ 0.23A] flowing thru the 100R and 5R in series, so what is the voltage drop across the 100R.?
E

Hint: V=I * R
 

Thread Starter

aeln269

Joined Oct 18, 2020
30
Ill be honest I dont remember how to calculate voltage drop though we did it a few weeks ago let me try and find information for it
 

ericgibbs

Joined Jan 29, 2010
11,122
hi,
OK,
So you know the battery voltage is 24V and you are dropping 23V across the 100R, so what voltage is at the top end of R4.?
E
 
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