Engineering Questions with Answers - Multiple Choice Questions
MCQs on Real Time Operating systems-1
1 - Question
MCQs on Operating Systems
Which of the following provides a buffer between the user and the low-level interfaces to the hardware?
a) operating system
b) kernel
c) software
d) hardware
View Answer
Explanation: The operating system is software which provides a buffer between the low-level interfaces to the hardware within the system and the user.
2 - Question
Which of the following enables the user to utilise the system efficiently?
a) kernel
b) operating system
c) software
d) hardware
View Answer
Explanation: The operating system is software that enables the users to utilise the system effectively.
3 - Question
Which of the following can make the application program hardware independent?
a) software
b) application manager
c) operating system
d) kernel
View Answer
Explanation: The operating system allows the software to be moved from one system to another and therefore, it can make the application program hardware independent. advertisement
4 - Question
Which of the following speed up the testing process?
a) kernel
b) software
c) application manager
d) program debugging tools
View Answer
Explanation: The program debugging tools can speed up the testing process which can make the processor faster.
5 - Question
Which of the following includes its own I/O routine?
a) hardware
b) kernel
c) operating system
d) application manager
View Answer
Explanation: An operating system is a software which includes its own I/o routine in order to drive the serial ports and the parallel ports.
6 - Question
Which forms the heart of the operating system?
a) kernel
b) applications
c) hardware
d) operating system
View Answer
Explanation: The kernel is the heart of the operating system. This can control the hardware and can deal with the interrupts, I/O systems, memory etc.
7 - Question
Which of the following locates a parameter block by using an address pointer?
a) OS
b) kernel
c) system
d) memory
View Answer
Explanation: The kernel is the heart of the operating system which can control the hardware and can deal with the interrupts, I/O systems, memory etc. It can also locate the parameter block by using an address pointer which is stored in the predetermined address register.
8 - Question
Which of the following are not dependent on the actual hardware performing the physical task?
a) applications
b) hardware
c) registers
d) parameter block
View Answer
Explanation: The kernel can locate the parameter block by using an address pointer which is stored in the predetermined address register. These parameter blocks are standard throughout the operating system, that is, they are not dependent on the actual hardware performing the physical task.
9 - Question
Which of the following bus can easily upgrade the system hardware?
a) control bus
b) data bus
c) VMEbus
d) bus interface unit
View Answer
Explanation: The software can be easily moved from one system to another which is more important for designing embedded systems, especially for those which use an industry standard bus such as VMEbus, in which the system hardware can be expanded or upgraded.
10 - Question
Which of the following is the first widely used operating system?
a) MS-DOS
b) windows XP
c) android
d) CP/M
View Answer
Explanation: The first widely used operating system is the CP/M which is developed for Intel 8080 and the 8”floppy disk system.
11 - Question
Which of the following is an example of a single task operating system?
a) android
b) windows
c) IOS
d) CP/M
View Answer
Explanation: The CP/M is a single task operating system, that is, only one task or an application can be executed at a time.
12 - Question
Which of the following becomes a limiting factor while an application program has to be complete?
a) memory
b) peripheral
c) input
d) output
View Answer
Explanation: The application program has to complete and the memory becomes a limiting factor, which can be solved by using program overlays.
13 - Question
Which of the following cannot carry implicit information?
a) semaphore
b) message passing
c) threads
d) process
View Answer
Explanation: The kernel in the real-time operating system which deals with the flag but cannot carry implicit information are called semaphores or events.
14 - Question
MCQs on Multitasking Operating Systems
Which of the following works by dividing the processor’s time?
a) single task operating system
b) multitask operating system
c) kernel
d) applications
View Answer
Explanation: The multitasking operating system works by dividing the processor’s time into different discrete time slots, that is, each application requires a defined number of time slots to complete its execution.
15 - Question
Which of the following decides which task can have the next time slot?
a) single task operating system
b) applications
c) kernel
d) software
View Answer
Explanation: The operating system kernel decides which task can have the next time slot. So instead of the task executing continuously until completion, the execution of the processor is interleaved with the other tasks.
16 - Question
Which of the following controls the time slicing mechanism in a multitasking operating system?
a) kernel
b) single tasking kernel
c) multitasking kernel
d) application manager
View Answer
Explanation: The multitasking operating systems are associated with the multitasking kernel which controls the time slicing mechanism. advertisement
17 - Question
Which of the following provides a time period for the context switch?
a) timer
b) counter
c) time slice
d) time machine
View Answer
Explanation: The time period required for each task for execution before it is stopped and replaced during a context switch is known as the time slice.
18 - Question
Which of the following can periodically trigger the context switch?
a) software interrupt
b) hardware interrupt
c) peripheral
d) memory
View Answer
Explanation: The multitasking operating systems are associated with the multitasking kernel which controls the time slicing mechanism. The time period required for each task for execution before it is stopped and replaced during a context switch is known as the time slice. These are periodically triggered by a hardware interrupt from the system timer.
19 - Question
Which interrupt provides system clock in the context switching?
a) software interrupt
b) hardware interrupt
c) peripheral
d) memory
View Answer
Explanation: The multitasking operating systems deals with the multitasking kernel which controls the time slicing mechanism and the time period required for each task for execution before it is stopped and replaced during a context switch is known as the time slice which are periodically triggered by a hardware interrupt from the system timer. This hardware interrupt provides the system clock in which several interrupts are executed and counted before a context switch is performed.
20 - Question
The special tale in the multitasking operating system is also known as
a) task control block
b) task access block
c) task address block
d) task allocating block
View Answer
Explanation: When a context switch is performed, the current program or task is interrupted, so the processor’s registers are saved in a special table which is known as task control block.
21 - Question
Which of the following stores all the task information that the system requires?
a) task access block
b) register
c) accumulator
d) task control block
View Answer
Explanation: The task control block stores all the task information that the system requires and this is done when the context switch is performed so that the currently running program is interrupted.
22 - Question
Which of the following contains all the task and their status?
a) register
b) ready list
c) access list
d) task list
View Answer
Explanation: The ‘ready’ list possesses all the information regarding a task, that is, all the task and its corresponding status which is used by the scheduler to decide which task should execute in the next time slice.
23 - Question
Which determines the sequence and the associated task’s priority?
a) scheduling algorithm
b) ready list
c) task control block
d) application register
View Answer
Explanation: The scheduling algorithm determines the sequence and an associated task’s priority. It also determines the present status of the task.
24 - Question
Which can control memory usage?
a) operating system
b) applications
c) hardware
d) kernel
View Answer
Explanation: The kernel can control the memory usage and it can also prevent the tasks from corrupting each other.
25 - Question
Which can control the memory sharing between the tasks?
a) kernel
b) application
c) software
d) OS
View Answer
Explanation: The kernel can control memory sharing between tasks which allow sharing common program modules.
26 - Question
Which of the following can implement the message passing and control?
a) application software
b) operating system
c) software
d) kernel
View Answer
Explanation: The kernel can implement the message passing and control which acts as a message passer and controller between the tasks.
27 - Question
How many types of messages are associated with the real-time operating system?
a) 2
b) 3
c) 4
d) 5
View Answer
Explanation: There are two basic types of messages associated with the real-time operating system. These are semaphores and messages.
28 - Question
Which of the following can carry information and control task?
a) semaphore
b) messages
c) flags
d) address message
View Answer
Explanation: The messages can carry information and it can also control the task regarding the real-time operating systems. These are also known as events.
29 - Question
MCQs on Task Swapping Methods
Which task swapping method does not require the time critical operations?
a) time slice
b) pre-emption
c) cooperative multitasking
d) schedule algorithm
View Answer
Explanation: Time-critical operations are not essential in the time slice mechanism. Time slice mechanism describes the task switching in a particular time slot.
30 - Question
Which task swap method works in a regular periodic point?
a) pre-emption
b) time slice
c) schedule algorithm
d) cooperative multitasking
View Answer
Explanation: The time slicing works by switching task in regular periodic points in time, that is, any task that needs to run next will have to wait until the current time slice is completed.
31 - Question
Which of the following determines the next task in the time slice method of task swapping?
a) scheduling program
b) scheduling application
c) scheduling algorithm
d) scheduling task
View Answer
Explanation: The time slice mechanism can also be used as a scheduling method in which the task to run next is determined by the scheduling algorithm. advertisement
32 - Question
Which of the following can be used to distribute the time slice across all the task?
a) timer
b) counter
c) round-robin
d) task slicing
View Answer
Explanation: The time slice based system uses fairness scheduler or round robin to distribute the time slices across all the tasks that need to run in a particular time slot.
33 - Question
What do a time slice period plus a context switch time of the processor determines?
a) scheduling task
b) scheduling algorithm
c) context task
d) context switch time
View Answer
Explanation: The context switch time of the processor along with the time slice period determines the context switch time of the system which is an important factor in system response, that is, the time period can be reduced to improve the context switching of the system which will increase the number of task switches.
34 - Question
Which can increase the number of task switches?
a) time period
b) frequency
c) time rate
d) number of cycles
View Answer
Explanation: The time period can be reduced to improve the context switching of the system which will increase the number of task switches.
35 - Question
Which mechanism is used behind the Windows 3.1?
a) time slice
b) pre-emption
c) cooperative multitasking
d) scheduling algorithm
View Answer
Explanation: The cooperative multitasking mechanism is used the Windows 3.1 but it is not applicable to the real-time operating systems.
36 - Question
Which of the following provides an illusion of multitasking?
a) single task operating system
b) multitasking operating system
c) cooperative multitasking
d) pre-emption
View Answer
Explanation: The cooperative multitasking co-operates between them which provides the illusion of multitasking. This is done by periodically executing the tasks.
37 - Question
Which task method follows a currently running task to be stopped by a higher priority task?
a) scheduling algorithm
b) time slice
c) cooperative multitasking
d) pre-emption
View Answer
Explanation: The pre-emption is an alternative method of the time slice where the currently running task can be stopped or preempted or switched out by a higher priority active task.
38 - Question
Which of the following requires programming within the application?
a) time slice
b) scheduling algorithm
c) pre-emption
d) cooperative multitasking
View Answer
Explanation: The cooperative multitasking requires programming within the application and the system can be destroyed by a single program which hogs all the processing power. Therefore, it is not applicable in the real-time operating system.
39 - Question
What does RMS stand for?
a) rate monotonic scheduling
b) rate machine scheduling
c) rate monotonic software
d) rate machine software
View Answer
Explanation: The rate monotonic scheduling is a method that is used to assign priority for a pre-emptive system such that the correct execution can be guaranteed.
40 - Question
Which of the following task swapping method is a better choice in the embedded systems design?
a) RMS
b) pre-emptive
c) cooperative multitasking
d) time slice
View Answer
Explanation: The pre-emptive method of task swapping is the first choice for embedded system design because of its better system response.
41 - Question
MCQs on Priority Inversion
Which of the following allows a lower priority task to run despite the higher priority task is active and waiting to preempt?
a) message queue
b) message passing
c) semaphore
d) priority inversion
View Answer
Explanation: The priority inversion mechanism where the lower priority task can continue to run despite there being a higher priority task active and waiting to preempt.
42 - Question
What happens to the interrupts in an interrupt service routine?
a) disable interrupt
b) enable interrupts
c) remains unchanged
d) ready state
View Answer
Explanation: In the interrupt service routine, all the other interrupts are disabled till the routine completes which can cause a problem if another interrupt is received and held pending. This can result in priority inversion.
43 - Question
Which of the following is a part of RTOS kernel?
a) memory
b) input
c) ISR
d) register
View Answer
Explanation: The ISR can send the message for the tasks and it is a part of RTOS kernel. advertisement
44 - Question
Which of the following is an industrial interconnection bus?
a) bus interface unit
b) data bus
c) address bus
d) VMEbus
View Answer
Explanation: The VMEbus is an interconnection bus which is used in the industrial control and many other real-time applications.
45 - Question
Which of the following supports seven interrupt priority level?
a) kernel
b) operating system
c) VMEbus
d) data bus
View Answer
Explanation: The VMEbus supports seven interrupt priority level which allows the prioritisation of the resources.
46 - Question
What type of interrupt handling is seen in multiprocessor applications?
a) centralised interrupt
b) handled by one MASTER
c) distributed handling
d) shared handling
View Answer
Explanation: The multiprocessor applications allows distributed handling in which the direct communication with the individual masters is possible.
47 - Question
Which of the following is an asynchronous bus?
a) VMEbus
b) timer
c) data bus
d) address bus
View Answer
Explanation: The VMEbus is based on Eurocard sizes and is asynchronous which is similar to the MC68000.
48 - Question
Which of the following is not a priority based?
a) priority inversion
b) message passing
c) fairness system
d) message queuing
View Answer
Explanation: The fairness system allows the system which requires different characteristics from those originally provided and the system response that is not a priority based. The fairness system is not a priority based on where the bus access is distributed across the requesting processors.
49 - Question
MCQs on Tasks,Threads and Process
Which of the following can be used to refer to entities within the RTOS?
a) threads
b) kernels
c) system
d) applications
View Answer
Explanation: The threads and processes can be used to refer to entities within the RTOS. They provide an interchangeable replacement for the task. They have a slight difference in their function. A process is a program in execution and it has its own address space whereas threads have a shared address space. The task can be defined as a set of instructions which can be loaded into the memory.
50 - Question
Which of the following defines the set of instructions loaded into the memory?
a) process
b) task
c) thread
d) system hardware
View Answer
Explanation: The task can be defined by the set of instructions which is loaded into the memory and it can split into two or more tasks.
51 - Question
Which of the following uses its own address space?
a) thread
b) process
c) task
d) kernel
View Answer
Explanation: Threads uses shared memory space and it uses the memory space of the process. advertisement
52 - Question
Which of the following does not uses a shared memory?
a) process
b) thread
c) task
d) kernel
View Answer
Explanation: The program in execution is known as the process. The process does not share the memory space but the threads have a shared memory address. When the CPU switches from process to another, the current information is stored in the process descriptor.
53 - Question
Which of the following can own and control the resources?
a) thread
b) task
c) system
d) peripheral
View Answer
Explanation: The task and process have several characteristics and one such is that the task or process can own or control resources and it has threads of execution which are the paths through the code.
54 - Question
Which can be supported if the task or process maintains a separate data area for each thread?
a) single thread system
b) mono thread system
c) multiple threads
d) dual threads
View Answer
Explanation: The multiple threads can be supported only if the process or task can maintain separate data areas for each thread.
55 - Question
Which of the following possesses threads of execution?
a) process
b) thread
c) kernel
d) operating system
View Answer
Explanation: The process has threads of execution which are the paths through the code.
56 - Question
Which of the following is inherited from the parent task?
a) task
b) process
c) thread
d) kernel
View Answer
Explanation: The threads are a part of the process, that is, it uses a shared memory of the process and therefore said that its resources are inherited from the parent process or task.
57 - Question
Which term is used to encompass more than a simple context switch?
a) process
b) single thread system
c) thread
d) multithread
View Answer
Explanation: The process includes the additional information which is used to encompass more than a simple context switch. This is similar to the task switching, that is why it is said that process and task are interchangeable.
58 - Question
Which can be considered as the lower level in the multitasking operating system?
a) process
b) task
c) threads
d) multi threads
View Answer
Explanation: In the multitasking operating system, the process and tasks form the higher level whereas the thread is the lower level. But in a simple operating system, there is no difference between the context switch of thread and the process.