Which is true? An ideal emf device has internal resistance and a real emf device does not. A real emf device sets up a potential difference and an ideal emf device does not. An ideal emf device sets up a potential difference and a real emf device does not. A real emf device has internal resistance and an ideal emf device does not.

A real emf device has internal resistance and an ideal emf device does not

Explanation:

What is EMF?

The electromotive force or potential difference or voltage is the reason behind the flow of current in a circuit.

What is Ideal emf device?

The ideal emf device is one which doesn't have any internal resistance and it provides a fixed emf regardless of the load current.

What is Real emf device?

But nothing is ideal in real world, A real emf device would have some internal resistance in series with the emf device.

Conclusion:

The internal resistance causes voltage drop therefore, as the load current changes, the voltage drop changes and hence device emf changes.

energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical means. do not understand what you are asking but hope this