What Is the Slope Resistance of a Zener Diode?

[aspsrilanka]

what is the mean of "slope resistance" of zener diode? Its parallel to diod or series?

 

[berkeman]

what is the mean of "slope resistance" of zener diode? Its parallel to diod or series?

Look at the plot of the Current versus Voltage for the diode in forward and revers bias. In reverse bias, where the Zener diode starts to conduct, there is a slope to the curve. That slope can be thought of as a "resistance", if you linearize (average) it over some range of reverse bias.