A zener of breakdown voltage VZ = 8 V and maximum Zener current, IZM = 10 mA is subjected to an input voltage Vi = 10 V with series resistance R = 100 Ω. In the given circuit RL represents the variable load resistance. The ratio of maximum and minimum value of RL is __________.
Solution and Explanation
The correct answer is 2
Minimum value of RL for which the diode is shorted is
\(\frac{R_L}{R_L}\)+100×10=8 ⇒RL=400 Ω
For maximum value of RL, current through diode is 10 mA.
So
\(i_R= i_{R_L} +I_{ZM}\)
\(\frac{2}{100}\)=\(\frac{8}{R_L}\)+10×10−3
10×10−3=\(\frac{8}{R_L}\)
RL = 800 Ω
So
\(\frac{R_{Lmax}}{R_{Lmin}}=\frac{800}{400}=2\)
So, ratio of maximum and minimum value of RL is 2
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GMC Azamgarh Admission 2025: Dates, Courses, Fees, Eligibility, SelectJuly 22, 2025Concepts Used:
Electric Current
Defining Electric Current
It is the rate of flow of electrons in a conductor. SI Unit - Ampere (A).
Electrons are negatively charged particles hence when they move a number of charges moves.
Note:- The ability of a particular substance to conduct electricity depends on the number of electrons that are able to move . Some of the materials allow current to flow better than others.
What is an Electromotive Force?
If a force acts on electrons to make them move in a particular direction, then up to some extent random motion of the electrons will be eliminated. An overall movement in one direction. The force which acts on the electrons to move them in a certain direction is known as electromotive force and its quantity is known as voltage and is measured in V.