Explore topic-wise MCQs in Current Affairs.

This section includes 568 Mcqs, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

451.

The number of d-electrons in Fe2+ (Z = 26) is not equal to that of

A. p-electrons in Ne(Z = 10)
B. s-electrons in Mg(Z = 12)
C. d-electrons in Fe(Z = 26)
D. p-electrons in CI(Z = 17)
Answer» E.
452.

The metal used to recover copper from a solution of copper sulphate is

A. Na
B. Ag
C. Hg
D. Fe
Answer» E.
453.

The most electronegative element among the following is

A. sodium
B. bromine
C. fluorine
D. oxygen
Answer» D. oxygen
454.

The number of moles of solute present in 1 kg of a solvent is called its

A. molality
B. molarity
C. normality
D. formality
Answer» B. molarity
455.

The nucleus of an atom consists of

A. electrons and neutrons
B. electrons and protons
C. protons and neutrons
D. All of the above
Answer» D. All of the above
456.

42 40 38 35 33 31 28

A. 25 22
B. 26 23
C. 26 24
D. 25 23
Answer» [{"answer":"3"}]. 25 22
457.

Look at this series: 8, 6, 9, 23, 87 , ... What number should come next?

A. 128
B. 226
C. 324
D. 429
Answer» [{"answer":"4"}]. 128
458.

Look at this series: 5.2, 4.8, 4.4, 4, ... What number should come next?

A. 3
B. 3.3
C. 3.5
D. 3.6
Answer» [{"answer":"4"}]. 3
459.

Look at this series: 2, 6, 18, 54, ... What number should come next?

A. 108
B. 148
C. 162
D. 216
Answer» [{"answer":"3"}]. 108
460.

Look at this series: 80, 10, 70, 15, 60, ... What number should come next?

A. 20
B. 25
C. 30
D. 50
Answer» [{"answer":"1"}]. 20
461.

Look at this series: 544, 509, 474, 439, ... What number should come next?

A. 404
B. 414
C. 420
D. 445
Answer» [{"answer":"1"}]. 404
462.

Look at this series: 201, 202, 204, 207, ... What number should come next?

A. 205
B. 208
C. 210
D. 211
Answer» [{"answer":"4"}]. 205
463.

This is an alternating multiplication and subtracting series: First, multiply by 2 and then subtract 8.

A. 11
B. 12
C. 13
D. 14
Answer» [{"answer":"2"}]. 11
464.

Look at this series: 14, 28, 20, 40, 32, 64, ... What number should come next?

A. 52
B. 56
C. 96
D. 128
Answer» [{"answer":"2"}]. 52
465.

Look at this series: 1.5, 2.3, 3.1, 3.9, ... What number should come next?

A. 15
B. 14
C. 13
D. 12
Answer» [{"answer":"1"}]. 15
466.

Look at this series: 31, 29, 24, 22, 17, ... What number should come next?

A. 15
B. 14
C. 13
D. 12
Answer» [{"answer":"1"}]. 15
467.

Look at this series: 8, 22, 8, 28, 8, ... What number should come next?

A. 9
B. 29
C. 32
D. 34
Answer» [{"answer":"4"}]. 9
468.

Look at this series: 3, 4, 7, 8, 11, 12, ... What number should come next?

A. 7
B. 10
C. 14
D. 15
Answer» [{"answer":"4"}]. 7
469.

Look at this series: 58, 52, 46, 40, 34, ... What number should come next?

A. 26
B. 28
C. 30
D. 32
Answer» [{"answer":"2"}]. 26
470.

Look at this series: 21, 9, 21, 11, 21, 13, 21, ... What number should come next?

A. 14
B. 15
C. 21
D. 23
Answer» [{"answer":"2"}]. 14
471.

Look at this series: 53, 53, 40, 40, 27, 27, ... What number should come next?

A. 12
B. 14
C. 27
D. 53
Answer» [{"answer":"2"}]. 12
472.

Look at this series: 22, 21, 23, 22, 24, 23, ... What number should come next?

A. 22
B. 24
C. 25
D. 26
Answer» [{"answer":"3"}]. 22
473.

Look at this series: 36, 34, 30, 28, 24, ... What number should come next?

A. 20
B. 22
C. 23
D. 26
Answer» [{"answer":"2"}]. 20
474.

Look at this series: 7, 10, 8, 11, 9, 12, ... What number should come next?

A. 7
B. 10
C. 12
D. 13
Answer» [{"answer":"2"}]. 7
475.

Look at this series: 2, 1, (1/2), (1/4), ... What number should come next?

A. (1/3)
B. (1/3)
C. (2/8)
D. (1/16)
Answer» [{"answer":"2"}]. (1/3)
476.

 In the Many to Many model when a thread performs a blocking system call

A. other threads are strictly prohibited from running
B. other threads are allowed to run
C. other threads only from other processes are allowed to run
D. None of these
Answer» C. other threads only from other processes are allowed to run
477.

In the Many to Many model true concurrency cannot be gained because 

A.  the kernel can schedule only one thread at a time
B. there are too many threads to handle
C.  it is hard to map threads with each other
D. None of these
Answer» B. there are too many threads to handle
478.

When is the Many to One model at an advantage ?

A. When the program does not need multi-threading
B. When the program has to be multi-threaded
C. When there is a single processor
D. None of these
Answer» B. When the program has to be multi-threaded
479.

Which of the following is the drawback of the One to One Model ?

A. increased concurrency provided by this model
B. decreased concurrency provided by this model
C. creating so many threads at once can crash the system
D. creating so many threads at once can crash the system
Answer» E.
480.

In the One to One model when a thread makes a blocking system call 

A. other threads are strictly prohibited from running
B. other threads are allowed to run
C. other threads only from other processes are allowed to run
D. None of these
Answer» C. other threads only from other processes are allowed to run
481.

 The One to One model allows 

A. increased concurrency
B. decreased concurrency
C. increased or decreased concurrency
D. concurrency equivalent to other models
Answer» B. decreased concurrency
482.

In the Many to One model, multiple threads are unable to run in parallel on multiprocessors because

A. only one thread can access the kernel at a time
B. many user threads have access to just one kernel thread
C. there is only one kernel thread
D. None of these
Answer» B. many user threads have access to just one kernel thread
483.

In the Many to One model, if a thread makes a blocking system call 

A. the entire process will be blocked
B. a part of the process will stay blocked, with the rest running
C.  the entire process will run
D. None of these
Answer» B. a part of the process will stay blocked, with the rest running
484.

The model in which one user-level thread is mapped to many kernel level threads is called

A. Many to One model
B. One to Many model
C. Many to Many model
D. One to One model
Answer» C. Many to Many model
485.

The model in which one kernel thread is mapped to many user-level threads is called :

A. Many to One model
B. One to Many model
C. Many to Many model
D. One to One model
Answer» B. One to Many model
486.

What is role of base/bound registers ?

A. They give starting address to a program
B. Program’s addresses are neatly confined to space between the base and the bound registers
C. They provide encrypted environment
D. This technique doesn’t protects a program’s address from modification by another user
Answer» C. They provide encrypted environment
487.

What is basic need in protecting memory in multi-user environment ?

A. We need two registers one ‘start’ and other ‘end’
B. We need a variable register
C. A fence register has to be used known as base register.
D. none of the mentioned
Answer» D. none of the mentioned
488.

 How can fence and relocation be used together ?

A. To each program address, the contents of fence register are added
B.
C. Both a and b
D. none of the mentioned
Answer» B.
489.

What is not true regarding ‘Fence’ ?

A. It is implemented via hardware register
B.  It doesn’t protect users from each other
C. It good to protect OS from abusive users
D. Its implementation is unrestricted and can take any amount of space in Operating 
Answer» E.
490.

Working set model for page replacement is based on the assumption of

A. modularity
B. locality
C. globalization
D. random access
Answer» C. globalization
491.

A process is thrashing if ?

A. it is spending more time paging than executing
B. it is spending less time paging than executing
C. page fault occurs
D. swapping can not take place
Answer» B. it is spending less time paging than executing
492.

Which algorithm chooses the page that has not been used for the longest period of time whenever the page required to be replaced?

A. first in first out algorithm
B. additional reference bit algorithm
C. least recently used algorithm
D. counting based page replacement algorithm
Answer» D. counting based page replacement algorithm
493.

In FIFO page replacement algorithm, when a page must be replaced

A. oldest page is chosen
B. newest page is chosen
C. random page is chosen
D. none of the mentioned
Answer» B. newest page is chosen
494.

 Effective access time is directly proportional to

A. page-fault rate
B. hit ratio
C. memory access time
D. none of the mentioned
Answer» B. hit ratio
495.

When a program tries to access a page that is mapped in address space but not loaded in physical memory, then

A. segmentation fault occurs
B. fatal error occurs
C. page fault occurs
D.  no error occurs
Answer» D.  no error occurs
496.

Swap space exists in ?

A. primary memory
B. secondary memory
C. CPU
D. secondary memory
Answer» C. CPU
497.

The pager concerns with the

A. individual page of a process
B. entire process
C. entire thread
D. first page of a process
Answer» B. entire process
498.

_____ is the concept in which a process is copied into main memory from the secondary memory according to the requirement.

A. Paging
B. Demand paging
C. Segmentation
D. Swapping
Answer» C. Segmentation
499.

Because of virtual memory, the memory can be shared among

A. This section of our 1000+ Operating System MCQs focuses on virtual memory concept of Operating System.
B. processes
C.  instructions
D. threads
Answer» B. processes
500.

The sum of first 45 natural numbers is:

A. 1035
B. 1280
C. 2070
D. 2140
Answer» [{"answer":"1"}]. 1035