What Value of R should be used in Figure if it is required that the voltage across R be 36V?

 

But first you need to show us your attempt.

 

As the voltage across R is needed to be 36V , similar will be voltage across 6KOHM resistor, so 6m Amp would be current through it,

If I know about the total current drawn from voltage source , I can, then, know the current through R resistor by current division principle, but I dont know the total current. Or if I know the value of R then combining R in parallel with 6K ohm resistor and then adding the equivalent with 2Kohm and 4Kohm, in this way I can get the current drawn from voltage source, but value of R is required and total current provided by voltage source is not given, how can I solve now?

 

But you know the voltage drop across 2kΩ resistor and 4kΩ resistor. Is this information not enough ?

 

How can I know the voltage drop across 2Kohm resistor and 4Kohm resistor?

I only know that voltage drop across both will be 90-36 V, but what will be voltage across each 2Kohm and 4Kohm individually? How can I know that when I don't know the current through them?

 

But 2kΩ and 4kΩ resistor are connected in series. So you know the current, right?

 

They are in series but 6Kohm resistor in parallel with R ohm is also in series with them when I dont know the value of R , how can I calculate current?

 

Do you know that in series circuit we have the same current ? Also we already know the voltage drops across 2kΩ and 4kΩ resistors.
So we can find total current.

 

Yeah , now I got it , thank you so much really I made such an stupid mistake

 

I got right answer

 

I'm glad that I could help.

 

..... I was such and stupid mistake

Don't blame it on your parents.

 

Typing error in excitement

 

Typing error in excitement

Yes I got that