AFCAT EKT Computer Science Mock Test - 4 - Computer Science Engineering (CSE) MCQ

An array is collection of variables that are accessed with an index number. The first element of the array is at index 0.

A byte is a unit of data that is eight binary digits (bits) long.

In computer storage, Belady’s anomaly proves that it is possible to have more page faults when increasing the no. of page frames while using the first in the first out (FIFO) page replacement algorithm.

Here, _aμ_w = 1.33

∴ Refractive index of air w.r. to water,

g = GM/R², for constant G and M

∴ (Δg / g) × 100 = -2 × (ΔR / R) × 100 = -2 × (-1)%

= +2%

∴ The value of g increases by 2%

X.25 is a standard for WAN communications that defines how connections between user devices and network devices are established and maintained. X.25 is designed to operate effectively regardless of the type of systems connected to the network. It is typically used in the packet-switched networks (PSNs) of common carriers, such as the telephone companies. Subscribers are charged based on their use of the network.

Since x → ∞, t → 0
∴ lim (x→∞) x² sin(1/x²) = lim (t→0) (sin t / t) = 1

MAN (Metropolitan Area Network) is a computer network that usually spans a city or a large campus.

Whereas WAN (wide area network) is a large network that interconnects many other networks spanning cities, countries or continents.

In an electrical power transformer, there are primary, secondary and may be tertiary windings. The performance of a transformer mainly depends upon the flux linkages between these windings. For efficient flux linking between these windings, one low reluctance magnetic path common to all windings should be provided in the transformer. This low reluctance magnetic path in transformer is known as core of transformer.

Loopback address is a special IP number (127.0.0.1) that is designated for the software loopback interface of a machine. The loopback interface has no hardware associated with it, and it is not physically connected to a network.

By conservation of momentum:
MV = (M/2) × 0 + (M/2) × v
⇒ v = 2V

Metadata is the data providing information about the other data.

When child sits on the rotating disc, his weight acts downwards and does not produce any torque. Hence the angular momentum of the system is conserved.

If we set input value of de-multiplexer to 1, it works as a decoder.

Hence decoder is a special case of a de-multiplexer.

By default , all members of a class declared with the “class” Keyword have private access for all its members. 

The round robin scheduling algorithm is designed especially for time-sharing systems. It gives each job a time slot or quantum (its allowance of CPU time) and interrupting the job if it is not completed by then. The job is resumed next time a time slot is assigned to that process.

In stack organized architecture push and pop instruction is needs a address field to specify the location of data for pushing into the stack and destination location during pop operation but for logic and arithmetic operation the instruction does not need any address field as it operates on the top two data available in the stack.

To disprove that f is surjective (by counter-example), we find a y ∈ R such that there

does not exist x ∈ Z with f(x) = y.

Let y = 0.5. Then, |x + 1| = 0.5 ⇒ x = - 0.5 or x = - 1.5; neither of these is an integer. Hence, there does not exist x 2 Z with f(x) = 0:5 and so f is not surjective.

To disprove that f is injective (by counter-example), we find an x, y ∈ Z such that

f(x) = f(y) but x ≠ y.

Let x = 1, y = - 3. Then f(1) = 2 = f(-3) but 1 ≠ -3. Thus, f is not injective.

Decipherment in cryptography refers to decryption which converts ciphertext (Secret or coded text) into plaintext (original text).

Modem (Modulator-Demodulator) performs modulation & Demodulation i.e. formats the computer data so it can travel over phone or cable lines. Also, Modem perform data compression. The bits are grouped together by modem, in order to compress them.

Cookie is a small piece of data sent from a website and stored in a user’s web browser while a user is browsing a website. It is used to maintain a session.

In IEEE-754 double precision number representation, number of exponent and mantissa bits respectively are 11 and 52, and 1 bit is used to represent sign.

Special theory of relativity treats problems involving inertial frame of reference.

Heat released by sun Q₁ = σAT₁⁴

As the temperature is doubled, T₂ = 2T₁

So Q₂ = σAT₂⁴ = σA(2T₁)⁴ = 16Q₁

A dynamo converts mechanical energy to electrical energy, whereas an motor converts electrical energy into mechanical energy.

Ethernet cabling is most commonly used in high-speed wired computer networks. Data can be transmitted over wireless access points, twisted pair coaxial or fiber optic cable at a speed of 10mbps to 1000mbps. Standardization of Internet connections (based on Ethernet communication) with speeds upto 100 Gigabit per second has just begun in 2009.

is a memory-management scheme that permits the physical address space of a process to be noncontiguous. Paging avoids external fragmentation and the need for compaction. It also solves the considerable problem of fitting memory chunks of varying sizes onto the backing store.

Address bus is unidirectional out of microprocessor it carries address which maps to a particular memory location.

Lexical analysis is the process of converting a sequence of characters into a sequence of tokens. Lexical analysis phase, builds literal table (created to describe all literals used in the source program); Identifier table (created to describe all identifiers used in the source program) and uniform symbol table ( created to represent the program as a string of tokens rather than of individual characters).

Shortest job first (SJF) can be implemented in pre-emptive or non- preemptive manner But SRTN is the preemptive version of SJF in which the scheduler always dispatches the ready process which was the shortest expected time to completion.

Note: SRTF(Shortest Remaining Time First) is same as SRTN.