The four semiconductor diodes used in a bridge rectifier circuit have forward resistance which can be considered constant at 0.1 and infinite reverse resistance. They

The four semiconductor diodes used in a bridge rectifier circuit have forward resistance which can be considered constant at 0.1Ω and infinite reverse resistance. 

They supply a mean current of 10 A to a resistive load from a sinusoidally varying alternating supply of 20V r.m.s. 

Determine the resistance of the load and the efficiency of the circuit.