# ohms law

Discussion in 'Homework Help' started by beemovie, Dec 31, 2008.

1. ### beemovie Thread Starter Member

Dec 19, 2008
12
0
hi !!!!!

I have just started studying electronics a few weeks ago and I have an assignment consisting of about 20 circuits but I have one in particular which is causing me some problems to solve I cant understand anything.CAN SOMEONE HELP ME GO THROUGH IT PLEASE ????
Check it out !!!!
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1)What is the reading of the milliammeter when the load resistor RL is shorted ?
2)What are the readings of the milliammeter when the load resistor RL is set to each of the following values 50ohms nad 50kilo ohms ?
3)With respect to number (2) which value of RL makes the current source appear stiff ??

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2. ### vvkannan Active Member

Aug 9, 2008
138
11
Hello beemovie
a) when the load resistor is shorted the entire current flows
through that path as it offers no resistance.
b)use current division rule to determint the values of current for different values of resistors.see here

c)a stiff current source is one in which the load resistor is <= .01 Rs so that the entire current appears to flow through the load and the source appears stiff and the error is 1 percent or less .

3. ### beemovie Thread Starter Member

Dec 19, 2008
12
0
hello vvkannan!!!

I may look selfish but can you please show me your working for question 2

thanks

4. ### vvkannan Active Member

Aug 9, 2008
138
11
Here's the current division formula
current through the load resistor = total current x Rs / (Rs + load resistance)
you know the resistance values and total current.
Hope you can solve it now.