Element 3D Question 90

Question:

[3D90] A 1 watt, 10 volt zener diode with the following characteristics: I min. = 5 mA, I max. = 95 mA, and Z = 8 ohms ; is to be used as part of a voltage regulator. Approximately what size current limiting resistor would set it's bias to the midpoint of it's operating range?
 
  a) 100 ohms.
  b) 200 ohms. [correct answer]
  c) 1 kilohms.
  d) 2 kilohms.

Challengers Excerpt:

This question looks like it is missing a supply voltage. Is it, or am I missing something?

It also looks like test question zeners have the amazing ability to exceed their Pd ratings and not have a problem!

  Although the challengers excerpt was for EL3D 91, it applied to this question as well.  It is easy to see how using technology caused this question and EL3D91 to become incomplete.
--- Joe

Response:

Your are correct.  It appears due diligence wasn't applied when the FCC created this question.

Recommendation:

Change the question to:

[3D90] A 1 watt, 10 volt zener diode with the following characteristics: I min. = 5 mA, I max. = 95 mA, and Z = 8 ohms ; is to be used as part of a voltage regulator with a 24 VDC source. Approximately what size current limiting resistor would set it's bias to the midpoint of it's operating range?
 
  a) 100 ohms.
  b) 200 ohms. [correct answer]
  c) 1 kilohms.
  d) 2 kilohms.