The circuit consists of two OP-AMP stages. The first stage is a non-inverting amplifier, while the second stage is an inverting amplifier.
Let v1 be the output of the first stage, and vout be the final output of the second stage.
The gain of the first stage is given by:
A1 = 1 + R2 / R1
The output of the first stage is:
v1 = A1 · vin = (1 + R2 / R1) · vin
Since it is a non-inverting amplifier, v1 is in-phase with vin.
The gain of the second stage is given by:
A2 = −R3 / R2
The final output is:
vout = A2 · v1 = (−R3 / R2) · v1
Since the second stage is an inverting amplifier, the final output vout is out-of-phase with vin.
The gain of the overall circuit is:
Atotal = A1 · A2 = (1 + R2 / R1) · (−R3 / R2)
For R1 = R2, the total gain is:
Atotal = (1 + 1) · (−R3 / R2) = −2 · (R3 / R2)
The gain is not unity under this condition.
Match the LIST-I with LIST-II
LIST-I | LIST-II |
---|---|
A. Brillouin Zone | Provides the understanding of the origin of allowed and forbidden bands in solids. |
B. Extended Zone Scheme | The electrons in a crystal behave like free electrons for most of the \( k \) values except when it approaches \( n\pi/a \). |
C. Periodic Zone Scheme | The E-k curve for several values of \( n \) reduced into the first zone for a simple cubic lattice with vanishing potential. |
D. Reduced Zone Scheme | The E-K curve is not continuous and has discontinuities at \( k = \pm n\pi/a \), where \( n=1,2,3,\dots \). |
Choose the correct answer from the options given below:
At a particular temperature T, Planck's energy density of black body radiation in terms of frequency is \(\rho_T(\nu) = 8 \times 10^{-18} \text{ J/m}^3 \text{ Hz}^{-1}\) at \(\nu = 3 \times 10^{14}\) Hz. Then Planck's energy density \(\rho_T(\lambda)\) at the corresponding wavelength (\(\lambda\)) has the value \rule{1cm}{0.15mm} \(\times 10^2 \text{ J/m}^4\). (in integer)
[Speed of light \(c = 3 \times 10^8\) m/s]
(Note: The unit for \(\rho_T(\nu)\) in the original problem was given as J/m³, which is dimensionally incorrect for a spectral density. The correct unit J/(m³·Hz) or J·s/m³ is used here for the solution.)