DSSSB TGT Computer Science Practice Set 1

Explanation

Java is strongly (and statically) typed: every variable must be declared with a type, and the compiler does not allow values of incompatible types to be mixed without an explicit cast.

Explanation

Options (b) and (c) are printed identically in the source book.

Explanation

Morphing smoothly transforms one image or shape into another through intermediate frames. Tweening only generates in-between frames of position or motion, and inverse kinematics deals with jointed movement.

Explanation

In immediate addressing the operand value itself is part of the instruction; in ADD R4, #3 the constant 3 (marked by #) is used directly, with no memory lookup.

Explanation

A CD-ROM stores data as pits along one continuous spiral track running from the centre outward, while hard disks and floppy disks use concentric circular tracks.

Explanation

The OS stores each process's state, program counter, registers, scheduling and memory information in its Process Control Block (PCB), which it uses to save and restore the process during context switches.

Explanation

RISC (Reduced Instruction Set Computer) keeps only a small set of simple, essential instructions that run in about one clock cycle each, which increases speed. CISC uses many complex instructions.

Explanation

Total bandwidth = 10 channels × 3000 Hz + 9 guard bands × 300 Hz = 30,000 + 2,700 = 32,700 Hz. Ten channels need only nine guard bands between them.

Explanation

The IT Act, 2000 was amended by the Information Technology (Amendment) Act, 2008, which added offences such as cyber terrorism and identity theft. This amended version is called the IT Act, 2008.

Explanation

random.randrange(100) returns an integer from 0 to 99 (the stop value is excluded). Adding 1 gives a range of 1 to 100.

Explanation

The data list has 2 values but the index has 3 labels. pandas cannot match the lengths, so it raises a ValueError ("Length of values does not match length of index").

Explanation

LS[::2] takes indexes 0, 2, 4, 6, giving [1, 2, 3, 5]. LS[::-2] starts from the last element and goes backwards in steps of 2, giving [4, 7, 8, 9]. Joined, they give [1, 2, 3, 5, 4, 7, 8, 9].

Explanation

NumPy subtracts arrays element by element: [12−10, 23−20] = [2 3]. It does not stack or combine the arrays.

Explanation

A variable assigned at the top level of a module is already global, so no global keyword is needed for that first assignment. The keyword is needed only when a function wants to rebind a global name.

Explanation

A modem (modulator-demodulator) converts digital data into analog signals for transmission over telephone lines and converts them back at the receiver. Switches, hubs and repeaters handle signals that stay digital.

Explanation

GPRS adds packet-switched data to 2G GSM networks. It sits between 2G and 3G, so it is called 2.5G technology.

Explanation

CELLPADDING sets the space between a cell's border and its content. CELLSPACING sets the space between neighbouring cells.

Explanation

FRAMEBORDER takes 1 or 0 (yes or no) and controls whether a border is shown around the frame. It does not set the border colour or the scrollbars.

Explanation

Answer as per the book's key (b). Note that S→next == NULL would normally mean the stack is empty, so this question is doubtful.

Explanation

Corrected: the book's key says (c), but (b) is the true statement. Binary search needs random access, so a linked list is unsuitable for it.

Explanation

a'b + ab' is 1 only when a and b differ, which is exactly the definition of XOR (a ⊕ b).

Explanation

The 1s fill the rows cd = 01 and cd = 11 for every value of ab. In both rows d = 1, while c and a, b change, so the expression is F = d.

Explanation

Opacity measures how solid a layer is. Lowering it to 0% makes the layer fully transparent, and raising it makes the layer more solid.

Explanation

Stealing a computer speaker is ordinary physical theft. No computer, network or data is used to commit the offence, so it is not a cyber crime.

Explanation

In Flash, Break Apart (Ctrl+B) splits a text block into separate letters, so each letter can be placed on its own layer and animated separately.

Explanation

The Library panel of a Flash file stores all its symbols, plus any imported bitmaps, sounds and videos, so they can be reused across the document.

Explanation

Video editing works on audio and video media streams and is not organised around stored records. Profile, result and inventory systems are classic database applications.

Explanation

The crow's foot (many) is on the E1 side and the plain (one) end is on the E2 side. Many E1 entities relate to one E2 entity, so the relationship is many-to-one.

Explanation

The loop body does constant work and runs N times, so the running time is linear, O(N). O(2N) also simplifies to O(N).

Explanation

Customer calls in a call centre are served in arrival order (first in, first out), so they form a queue, not a hierarchy. Directories, a table of contents and arithmetic expressions are naturally hierarchical trees.

Explanation

Multiplication and division are done before addition and subtraction: 2*5 = 10 and 32/8 = 4, so 3 + 10 − 4 = 9.

Explanation

Brackets are evaluated first. Among the logical operators, NOT has the highest precedence, then AND, then OR.

Explanation

In transactional memory, a memory transaction is a sequence of memory read-write operations that is atomic: either all of them take effect (commit) or none do.

Explanation

Minterms 0, 4, 8 and 12 are exactly the cells where Y = 0 and Z = 0, whatever W and X are. These four cells form one group, so F = Y'Z'.

Explanation

Perspective makes objects that are farther away appear proportionally smaller, which gives a sense of depth in a two-dimensional image.

Explanation

A computer game responds to the player's input, so it is interactive. Radio, TV talk shows and newspapers are one-way media for the audience.

Explanation

In the buddy system, when a block is freed, it can be quickly merged with its free buddy to form a larger segment. This merging is called coalescing.

Explanation

Positioning time is seek time plus rotational latency. Seek time is the time to move the disk arm to the desired cylinder, and rotational latency is the wait for the sector to rotate under the head.

Explanation

Sorting is defined as re-arranging a given set of objects in a specific order (Wirth's definition). The other options describe why sorting is useful, not what sorting is.

Explanation

The figure compares pairs, moves the smaller key up each level and puts the minimum (06) at the root. This tournament-style structure is tree (tournament) sort.

Explanation

Student S1; creates an object with no arguments, so the default constructor is called. Student S2 = S1; initialises a new object from an existing one, so the copy constructor is called.

Explanation

Cache is a small, fast memory between the CPU and main memory. It gives near-register speed for frequently used data, while the large cheaper main memory provides the size.

Explanation

Binary search halves the list at each step, and 32 = 2⁵, so it takes about log₂32 = 5 comparisons. Strictly, the worst case is ⌊log₂32⌋ + 1 = 6, but 6 is not an option, so the intended answer is 5.

Explanation

132A in hex = 0001 0011 0010 1010 in binary. Regrouping in 3s from the right gives 1 001 100 101 010 = 11452 in octal.

Explanation

Linear search may have to check every one of the n elements in the worst case, so it takes O(n) time.

Explanation

A natural join takes the Cartesian product, keeps the rows where common attributes are equal (selection), then projects away the duplicate columns. So it is a projection of a filtered Cartesian product.

Explanation

Demand paging (virtual memory) loads pages only when they are needed, so a program larger than physical memory can still run. Thrashing is a performance problem, not a technique.

Explanation

Inorder traversal visits left subtree, root, then right subtree. Left subtree gives a + b * d, then the root −, then the right subtree e / f, giving a + b * d − e/f.

Explanation

Good modular design aims for low coupling (little dependence between modules) and high cohesion (each module focuses on one task).

Explanation

A missing person_ID breaks entity integrity, because a primary key cannot be null. An age of −45 is outside the valid domain, so domain integrity is also broken.

Explanation

Inheritance flows from the base class to the derived class. The public and protected members of point are inherited into circle, not the other way round, so statement D is false.

Explanation

In Java, new int[4][5] creates 4 rows and 5 columns. Declarations like int array[4][5] are not valid Java, and [5][4] has the dimensions reversed.

Explanation

Operands are pushed onto a stack. When an operator is read, the top two operands are popped, the operator is applied and the result is pushed back, so a stack is the natural structure for postfix evaluation.

Explanation

The main goal of OOP is reusability: classes, inheritance and polymorphism let existing code be reused and extended.

Explanation

EAT = 0.8 × 100 + 0.2 × 400 = 80 + 80 = 160 ns.

Explanation

Since 22 > 15 is true, the conditional operator picks x + y = 22 + 15 = 37, which is assigned to x.

Explanation

for(; f ;) has no update expression of its own, and f starts at 1 and is incremented each time by f++. f never becomes 0 in normal counting, so the condition stays true and the loop runs forever.

Explanation

Unordered list bullets in HTML (the type attribute) can be disc, square or circle. Triangle is not a standard bullet type.

Explanation

In the client-server model, the client sends a request for data or a service, and the server processes the request and returns the result.

Explanation

A class whose objects are created dynamically, or that allocates memory with new, needs a destructor to free that memory. Otherwise the memory leaks.

Explanation

A Von Neumann machine runs one instruction stream on one data stream at a time, which in Flynn's classification is SISD.

Explanation

(A) is wrong because ROM is non-volatile. (C) is wrong because RAM includes both static and dynamic RAM. (B) and (D) are true.

Explanation

Pulse code modulation samples, quantises and encodes a signal into binary pulses, giving a digital signal. AM, FM and ASK modulate an analog carrier.

Explanation

Networks allow resource sharing, improve reliability and availability through redundancy, and improve performance by spreading load. All three are advantages.

Explanation

A Wide Area Network covers large geographical areas such as cities or countries. A LAN covers a single building or campus.

Explanation

In a slotted ring, a station may transmit only when it holds an empty slot or token circulating on the ring. CSMA/CD is a contention (random access) protocol.

Explanation

The z-buffer method stores a depth value for every pixel, so it can handle any surface for which depth can be computed at each pixel, including non-polygonal and non-planar patches, with no sorting needed.

Explanation

Raster images are grids of pixels, commonly called bitmaps (a pixmap is the multi-bit-per-pixel form).

Explanation

Scaling multiplies coordinates by scale factors, which changes the size of the object. Translation changes the location.

Explanation

Declaring the formal (reference) parameters as const lets the function read the caller's data without being able to modify it.

Explanation

C supports only call by value. Even a pointer is passed by value (a copy of the address); call by reference is only simulated by using that address.

Explanation

A width in %4s limits input: scanf reads at most 4 non-whitespace characters into str. It may read fewer if whitespace comes first.

Explanation

A[2] is an int pointer, A[2][3] is an int reached through it, and B[2][3] is an int, so all three can be assigned. B[1] is an array (int[10]), and an array cannot be assigned, so only I, II and IV are valid.

Explanation

printf runs before the if statement, so continue only skips the (empty) rest of the loop body. Every value from 1 to 5 is printed: 12345.

Explanation

When users get navigational control and can move through the content in any order, the multimedia project is non-linear and interactive.

Explanation

Baud rate = 1000 signal units per second. Bit rate = baud × bits per unit = 1000 × 4 = 4000 bps.

Explanation

ASP.NET code runs on the IIS server, and only the resulting HTML is sent to the browser. Viewing the page source shows pure HTML.

Explanation

Memory allocated with new[] for an array must be freed with delete [] pp, so that the whole array is released and destructors run for every element.

Explanation

With n processes each needing k units, n(k−1) + 1 units guarantee no deadlock: 3 × (2−1) + 1 = 4.

Explanation

4096 = 2¹², which in binary is 1 followed by twelve 0s. That needs 13 bits (12 bits can go only up to 4095).

Explanation

Java's garbage collector automatically reclaims the memory of objects that are no longer referenced by any part of the program.

Explanation

DTD stands for Document Type Definition. It defines the legal elements and attributes of an XML or XHTML document.

Explanation

SMTP (Simple Mail Transfer Protocol) transfers e-mail between mail servers. HTTP is for web pages, FTP for files and SNMP for network management.

Explanation

OLE is Object Linking and Embedding, Microsoft's technology for linking or embedding objects from one application in a document of another.

Explanation

B ⊕ C = B ⊕ (A ⊕ B) = A ⊕ (B ⊕ B) = A ⊕ 0 = A.

Explanation

The first OR gate gives A + B', which is ANDed with C' to give (A + B')·C'. This result is ORed with D, so the output is (A + B')·C' + D.

Explanation

Python dictionaries have pop(), popitem() and get(), but no remove() method. remove() belongs to lists and sets.

Explanation

Closing cash = 4,00,000 + 3,20,000 − 2,80,000 = ₹4,40,000. Outstanding salary has not been paid in cash, so it does not reduce the cash balance.

Explanation

Closing balance = opening + receipts − payments = 6,00,000 + 2,50,000 − 3,20,000 = ₹5,30,000.

Explanation

NEP 2020 states that the M.Phil. programme shall be discontinued.

Explanation

Adolescence is called the period of "stress and storm" (G. Stanley Hall), because of rapid physical, emotional and social changes.

Explanation

Automatically giving the boy an airplane, a toy assumed to be "for boys", reflects a gender stereotype.

Explanation

Bloom's taxonomy describes three learning domains: cognitive, affective and psychomotor. Spiritual is not one of them.

Explanation

Family type (nuclear), urbanization and religious institutions are socio-cultural influences on a child. Examinations are part of the school system, not a socio-cultural factor.

Explanation

The tribal child is excluded from peer groups and his interests are ignored by the teacher, which pushes him to the edge of the group. This is marginalization.

Explanation

Evaluation means judging or critiquing, so verbs such as criticise, judge and appraise belong to it. Define and identify are knowledge-level verbs.

Explanation

Education policies framed by the government and authorities belong to the political dimension of the socio-cultural environment.

Explanation

Later childhood (about 6-12 years) is called the "gang age", because children like to form peer groups.

Explanation

Moral ideas such as honesty, empathy and idealism develop strongly in adolescence, along with abstract thinking.

Explanation

Adolescents tend to daydream and fantasise and to live in an imaginary, idealised world, so this stage is described as the child becoming "unreal".