A zener of breakdown voltage V_Z = 8V and maximum zener current, I_ZM = 10mA is subjected to an input voltage V_i = 10V with series resistance R = 100 $\Omega$  In the given circuit R_L represents the variable load resistance. The ratio maximum and minimum value of R_L is__________.

 

Across zener diode & RL

8 = I_LR_L

8 = $\left(20-10\right)R_{L\left(max\right)}$

$R_{Lmax}=\frac{8}{10}k\Omega$

At max current in loop (1)

10 = i_max R + 8

i_max = $\frac{2}{R}=\frac{2}{100}=0.02A$

= 20 mA

R_L (max) = $\frac{8}{10}k\Omega$

At minimum curre3nt through zener

i_max R_L (minimum) = 8

R_L (minimum) = $\frac{8}{20}k\Omega$

$\frac{R_{Lmax}}{R_{Lmin}}=2$

 

<p>Across zener diode &amp; RL</p><p>8 = I_LR_L</p><p>8 =&nbsp;<math><mrow><mrow><mo> (</mo><mrow><mn>2</mn><mn>0</mn><mo>−</mo><mn>1</mn><mn>0</mn></mrow><mo>)</mo></mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>L</mi><mrow><mo> (</mo><mrow><mi>m</mi><mi>a</mi><mi>x</mi></mrow><mo>)</mo></mrow></mrow></msub></mrow></math></p><p><math><mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>L</mi><mi>m</mi><mi>a</mi><mi>x</mi></mrow></msub><mo>=</mo><mfrac><mrow><mn>8</mn></mrow><mrow><mn>1</mn><mn>0</mn></mrow></mfrac><mi>k</mi><mi>Ω</mi></mrow></math></p><p>At max current in loop (1)</p><p>10 = i_max R + 8</p><p>i_max=&nbsp;<math><mrow><mfrac><mrow><mn>2</mn></mrow><mrow><mi>R</mi></mrow></mfrac><mo>=</mo><mfrac><mrow><mn>2</mn></mrow><mrow><mn>1</mn><mn>0</mn><mn>0</mn></mrow></mfrac><mo>=</mo><mn>0</mn><mo>.</mo><mn>0</mn><mn>2</mn><mi>A</mi></mrow></math></p><p>= 20 mA</p><p>R_L (max) =&nbsp;<math><mrow><mfrac><mrow><mn>8</mn></mrow><mrow><mn>1</mn><mn>0</mn></mrow></mfrac><mi>k</mi><mi>Ω</mi></mrow></math></p><p>At minimum curre3nt through zener</p><p>i_max R_L (minimum) = 8</p><p>R_L (minimum) =&nbsp;<math><mrow><mfrac><mrow><mn>8</mn></mrow><mrow><mn>2</mn><mn>0</mn></mrow></mfrac><mi>k</mi><mi>Ω</mi></mrow></math></p><p><math><mrow><mfrac><mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>L</mi><mi>m</mi><mi>a</mi><mi>x</mi></mrow></msub></mrow><mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>L</mi><mi>m</mi><mi>i</mi><mi>n</mi></mrow></msub></mrow></mfrac><mo>=</mo><mn>2</mn></mrow></math></p><div class="photo-widget-full"><div class="figure"><picture><source srcset="" media="(max-width: 500px)"><img src="https://images.shiksha.com/mediadata/images/1753068887phpKwkaDT.jpeg" alt="" width="456" height="256" loading="lazy"></picture></div></div><p>&nbsp;</p>

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