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Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

The maximum frequency at which an op-amp may operate depends on the _____.

  1. bandwidth (BW)

  2. slew rate (SR)

  3. unity-gain bandwidth

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The maximum operating frequency of an op-amp is limited by its bandwidth, slew rate, and unity-gain bandwidth, as these parameters define how fast the output can change and the frequency range over which it can amplify.

Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

An operational amplifier is a _____ gain and _____ bandwidth differential amplifier.

  1. very low, narrow

  2. low, wide

  3. medium, narrow

  4. very high, wide
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An ideal operational amplifier is characterized by very high open-loop gain and a very wide bandwidth, allowing it to be used in various applications with feedback.

Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

Pick out the correct option from the below for an opamp:

  1. output impedance= 75 ohms, input impedance = 1 M ohm and bandwidth = 5kHz

  2. output impedance= 75 ohms, input impedance = 1000 M ohm and bandwidth = 5kHz

  3. output impedance= 750 ohms, input impedance = 1 M ohm and bandwidth = 5kHz

  4. output impedance= 750 ohms, input impedance = 1 M ohm and bandwidth = 500 MHz
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A typical operational amplifier has very high input impedance (often in the range of Mega-ohms or Giga-ohms) and low output impedance (typically less than 100 ohms).

Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

The output of a particular Op-amp increases 8V in 12s. The slew rate is .

  1. $90 V/\mu s$

  2. $0.67 V/\mu s$

  3. $1.5 V/\mu s$

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Given,

$\triangle V=8V$
$\triangle t=12 s$
To find, Slew rate$=?$
Slew rate is defined as the voltage change in $\triangle V$ with respect to changing time $\triangle t$
$\therefore$ Slew rate $=\cfrac{\triangle V}{\triangle t}$
$\Rightarrow $ Slew rate$=\cfrac{8V}{12s}$
$\Rightarrow$ Slew rate$=0.666$
$\Rightarrow$ Slew Rate$\simeq 0.67$

Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

 Which among the following amplifier circuit exhibit the output voltage in the form of phase inversion?

  1. Adder

  2. Substractor

  3. Integrator

  4. Differentiator
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In any adder circuitry of Op-amp, the output voltage must be equivalent to the summation of all input voltages where each input voltage is a multiple of constant gain factor. This circuit is usually more similar to inverting scalar type of amplifier with an exception of possessing more than one input. Therefore, output voltage of adder or summer Op-amp is phase inverted.

Referring to subtractor, integrator and differentiator amplifiers, the output voltage of subtractor deals with the difference between two input signals, while integrator generates its output voltage in terms of integral of input voltage whereas the output voltage of differentiator is proportional to change in input in accordance to time.

Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

Which among the following are the major responsible reasons for the cause of 'Slew Rate'?

  1. Current limiting

  2. Saturation of internal stages due to application of high frequency & amplitude signal

  3. Both a & b

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Slew rate is limited by the internal current available to charge compensation capacitors and the saturation of internal stages when driven by high-frequency or high-amplitude signals.

Multiple choice the operational amplifier (op-amp) electronics physics properties of an ideal op-amp

Which among the following is also used as a buffer or an isolation amplifier?

  1. Inverting amplifier

  2. Non-inverting amplifier

  3. Unity Follower

  4. Emitter Follower
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Unity Follower circuit provides buffering or can be also used as an isolation amplifier which has a provision to obtain a gain at unity despite the requisite of any phase reversal. Emitter follower circuit is also semantic to unity follower only with an exception of gain which is in very much proximity of being absolutely equal to 1 (unity level). 

Unity Follower is supposed to be used as buffer since it becomes quite feasible to transfer the input voltage in the form of output voltage along with the prevention of load resistance from loading down to input source simultaneously. This becomes possible because the value of input resistance tends to infinity & output resistance equals to zero.

Multiple choice physics simple harmonic motion representing shm with circular motion shm as projection of circular motion simple harmonic motion (shm) as a projection of uniform circular motion

A force acts on a $30$gm particle in such a way that the position of the particle as a function of time is given by $x=3t-4t^2+t^3$, where x is in metres and t is in seconds. The work done during the first $4$ second is?

  1. $2.88$J

  2. $450$mJ

  3. $490$mJ

  4. $530$mJ
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$M=20gm=0.020kg$

$x=3t-4t²+t³m$
$v=dx/dt=3-8t+3t²m/s$
$a=dv/dt=-8+6tm/s²$
$Force=ma=0.120t-0.160N$
$Workdone=dW=Fdx=F\ast \frac { dx }{ dt } \ast dt=(0.120t-0.160)\ast (3-8t+3t²)dt=0.360t³-1.440t²+1.640t-0.480$
$W=0.090t⁴-0.490t³+0.82t²-0.480t=2.88J$

Multiple choice physics simple harmonic motion representing shm with circular motion shm as projection of circular motion simple harmonic motion (shm) as a projection of uniform circular motion

A wheel of radius $1$ meters rolls forward half a revolution on a horizontal ground. The magnitude of the displacement of the point of the wheel initially in contact with the ground is:

  1. $2 \pi$

  2. $\sqrt 2 \pi$

  3. $\sqrt {{\pi ^2} + 4} $

  4. $\pi$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Let fro $A$ to $B$, where complete half a rotation.
we have,
$PQ=\alpha =$ half circumference $=\pi \ m$
and $P' Q=$ diameter $=2\ m$
so we have displacement of $P$
$x=|PP;|=\sqrt {PQ^2 +P; Q^2}$ (Pythagoras theorem)
$\Rightarrow \ x=\sqrt {\pi^2 +4}m$