Modern Physics Ques 230
- A diode detector is used to detect an amplitude modulated wave of $60 \%$ modulation by using a condenser of capacity $250 $ $pF$ in parallel with a load resistance $100 $ $k \Omega$. Find the maximum modulated frequency which could be detected by it.
(2013 Main)
(a) $10.62 $ $MHz$
(b) $10.62$ $ kHz$
(c) $5.31 $ $MHz$
(d) $5.31 $ $kHz$
Show Answer
Answer:
Correct Answer: 230.(b)
Solution:
Formula:
The higher frequency which can be detected with tolerable distortion is
$ \begin{aligned} f & =\frac{1}{2 \pi m _a R C}=\frac{1}{2 \pi \times 0.6 \times 2.5 \times 10^{-5}} Hz \\ & =\frac{100 \times 10^{4}}{25 \times 1.2 \pi} Hz=\frac{4}{1.2 \pi} \times 10^{4} Hz=10.61 kHz \end{aligned} $
BETA
