What is the value of the load resistor?

[boxman]

Homework Statement

The internal resistance of a high voltage power supply is 24 MΩ and the output is set so that the potential difference across the output when on open circuit is 4000 V? When a load resistor RL is connected across the supply the voltage across RL is 3000 V.

What is the value of the load resistor?

Relevant Equations

I am not sure what equation to use.

But I think the answer is 32, is it correct?

 

[kuruman]

Hi @boxman and welcome to PF.

According to forum rules you must show at least an effort towards the answer. Perhaps you could explain what led you to think that the answer is 32 and not something else?

 

[boxman]

actually I rewatched the recording of the lecture and realized the answer was 72. But sorry about the low effort post its my first time using this forum and was unaware of the rules! :)

 

[DaveE]

72? 72 what? Volts? Kilograms? Units do actually matter in the real world.

 

[berkeman]

Homework Statement:: The internal resistance of a high voltage power supply is 24 MΩ

Are you sure about the 24 MΩ number? That does not look right.