four loads are connected in series across 110 volts DC .the loads fail to operate .a voltmeter in succesion across each divice reads 0 across the first 3 loads and 110volts across the fourth load.what circuit fault is indicated at the fourth load?

 

I can only think of one, the fourth load has become an infinitely large resistor which is another term for open circuit.

 

Imagine the four loads are light globes.

What fault condition in the 4th globe is likely to mean that none of them glow?

Does that condition lead to the same observations stated for the four globe voltages?

 

Doesn't this happen with old Christmas lights? hint-hint