Full Test 3 - EKT EEE - AFCAT MCQ

Let,

Now, we know that, 
Thus the integral can also be written as

Adding the above two integral equations, we get
 

 2I = 0

∴ I = 0

From the determinant formula, vector area of parallelogram 

We know that 1 + ω + ω² = 0 and ω³= 1 then

(1−ω⁸)(1−ω⁴)(1−ω²)(1−ω)=(1−ω²)(1−ω)(1−ω²)(1−ω)
=(1−ω²−ω+ω³)(1−ω²−ω+ω³)
=(2−(ω+ω²))(2−(ω+ω²))
=(2−(−1))(2−(−1))=9

Apply inverse Laplace transform we get f(t)= e^−5t−5te^−5t=e^−5t(1−5t)

Equilibrium is the status of the body when it is subjected to a system of forces. If the resultant force is equal to zero it implies that the net effect of the system of forces is zero this represents the state of equilibrium.

Mutual inductance of the pair of coils depends on the distance between two coils and geometry of two coils. The rate of change of current impacts the emf in coil. 

• For every material, there is a temperature specific to it known as its Curie temperature
• Above curie temperature, they lose their magnetic properties

In series the equivalent capacitance will be C = 1.6 μF. The charge will be same on each capacitor. Its value will be Q = CV = 1.6 × 10^-6  × 300 = 4.8 × 10^-4 C. The potential difference across C₁ and C₂ will be 240 V and 60 V respectively. The energy stored in the system will be 1/2CV² = 7.2 × 10^-2 J.

Cathode rays are stream of electrons observed in vacuum tubes. Rest all are electromagnetic waves in nature.

In trimetric projection, trimetric scales are used in which three perpendicular edges of the object make different angles with POP

The feedback amplification factor is given by   

where A is open loop gain and βA is loop gain.

As feedback increases the gain decreases thereby bandwidth increases since gain bandwidth product of Op - amp is constant, also feedback increases input impedance while decreasing output impedance.

In this problem compared to non - inverting amplifier with unity gain the 100 gain amplifier has less negative feedback leading to leading to lesser bandwidth and input impedance

The sensitivity of feedback amplifier to Op - amp amplification factor variances is given by

Therefore compared to unity gain amplifier 100 gain amplifier is more sensitive to changes in open loop Op - amp gain.

In a comparator if V⁺ > V^- then output is Vsat+ and if V⁺ < V^- then output is V_sat^-. In the question V^- is set to be ground, hence when during positive cycle of input sinusoid we get output as V_sat⁺ and V_sat^- during negative cycle. The overall output is a square wave.

We know that V_o=A(V₂−V₁)

−20=1000(10−V₁)
∴ V₁=10.02v
Common mode input voltage = 

In CC configuration the input resistance is high and output resistance is low.

Voltage gain is close to unity

To represent a decimal number 35 in binary, the minimum number of bits required are 6. Its binary representation is 100011.

For Binary addition use the following rule:

0 + 0 = 0

0 + 1 = 1

1 + 0 = 1

1 + 1 = 0 and a carry = 1

So, using these rules the binary addition of 1001 and 1101 gives 10110.

NOR gate is logically equivalent to an OR gate followed by an inverter. The logic or Boolean expression given for a logic NOR gate is that for Logical Multiplication which it performs on the complements of the inputs.

Boolean expression for A NOR B which gives output Q is

NOR gate

XNOR gate

A universal gate is a gate which can implement any Boolean function without need to use any other gate type. The NAND and NOR gates are universal gates. That means we can implement a whole logic whatever you can implement using AND, OR, Invert combination can be implement using NAND gates alone 

A reverse anode to cathode voltage will tend to interrupt the normal cycle and turn off the SCR. This way is also known as forced commutation.

SCR is a unidirectional switch since the gate current can only be positive and it operates in only one quadrant of I-V characteristics.

In induction motor, the rotor has fan blades to circulate cooling air through the motor frame.

A step up transformer is one in which the voltage in secondary side is more than that of primary side. However, the KVA remains the same.

In a conductor, the forbidden band is missing and the conduction band and valance band are overlapped. Therefore, no holes can be created in a metal.

In a P-type semiconductor the Fermi level is close to valence band while in n-type the Fermi level is closer to conduction band. Only in intrinsic semiconductor it is at center of conduction and valence band.

A MOSFET is a voltage controlled device and requires only a small input current. This is because of the fact that gate circuit impedance in MOSFET is extremely high, of the order of 10⁹ ohm.

Typically for a pnp or npn transistor, the current gain (α) is the ratio of the DC collector current to the DC emitter current. It is near to unity.

The P ⁺ N diode has heavily doped P- region. Under forward bias electrons are injected from N region to P region and holes are injected form P region into the N region. These injected carries become minority carriers in the other region and recombine with the majority carriers there and decay exponentially with distance. The switching speed of P ⁺ N (heavily doped P – region) junction depends on the life time (τ) of the majority carriers (i.e. electrons) in the N – region which is lightly doped region.