Find the db gain of an amplifier whose input voltage is 0.7 volts and whose output voltage is 17 volts.
A) $\quad 1.39 \mathrm { db }$
B) $\quad 63.8 \mathrm { db }$
C) $\quad 27.71 \mathrm { db }$
D) $\quad - 63.8 \mathrm { db }$
E) $\quad 3 \mathrm { db }$

Question

Find the db gain of an amplifier whose input voltage is 0.7 volts and whose output voltage is 17 volts. 
A) $\quad 1.39 \mathrm { db }$
B) $\quad 63.8 \mathrm { db }$
C) $\quad 27.71 \mathrm { db }$
D) $\quad - 63.8 \mathrm { db }$
E) $\quad 3 \mathrm { db }$

Quizplus · Accepted Answer

The gain in dB can be calculated using the formula $20 \log_{10} \left( \frac{V_{\text{out}}}{V_{\text{in}}} \right)$. Substituting $V_{\text{out}} = 17$ volts and $V_{\text{in}} = 0.7$ volts gives $20 \log_{10} \left( \frac{17}{0.7} \right) \approx 27.71 \, \text{dB}$.

Find the Db Gain of an Amplifier Whose Input Voltage 1.39db\quad 1.39 \mathrm { db }1.39db

Find the Db Gain of an Amplifier Whose Input Voltage $\quad 1.39 \mathrm { db }$