Practice 7.1 Control with authentic IB Computer Science (CS) exam questions for both SL and HL students. This question bank mirrors Paper 1, 2, 3 structure, covering key topics like programming concepts, algorithms, and data structures. Get instant solutions, detailed explanations, and build exam confidence with questions in the style of IB examiners.
A number of devices in and around the home can be operated by control systems.
A home owner wishes to install automatic lights to illuminate a water fountain in her garden. These lights will automatically turn on at sunset and turn off at sunrise.
Explain the concept of feedback, with respect to computer control systems in general.
The home owner has also installed a control system that waters the flowerbeds in the garden. This system aims to maintain the water content of the flowerbeds between a minimum and a maximum value. However, the system is only activated when the light intensity is below a certain level.
Outline the algorithm involved in controlling the watering system described above.
Describe two hardware components that would be an essential part of this control system.
Outline one feature of autonomous agents.
A mobile phone has been developed with its own dedicated operating system and is to be used as part of a smart home system in Singapore. The smart home system includes:
Identify two functions of an operating system.
Explain how sensors and microprocessors are used to ensure that the air conditioning system is able to maintain a constant temperature in the smart house.
Explain one benefit of using a dedicated operating system on the mobile phone instead of a generic operating system.
The developers of the smart home system are considering developing a smart home system that uses a distributed control system to manage the temperature.
Contrast the use of a distributed air conditioning system with a centralized air conditioning system for maintaining a constant temperature in the smart home.
A rail transport company uses a global positioning system (GPS) to determine a train's position.
The GPS data is used to provide real-time arrival data on video displays in train stations.
The GPS data is made publicly available so that software developers can use it to build apps.
The mobile application ATrainAway uses the real-time train GPS data as well as the GPS data from the user's smartphone.
State one data item concerning the arrival of a train that may be provided on the video display.
Explain how GPS works.
Outline two pieces of information that the ATrainAway application could provide to the user.
Outline how sensors can be used in combination with GPS to provide more accurate arrival data.
Discuss the advantages and disadvantages of using GPS in transportation systems.
A biotechnology company owns a resource centre which collects and classifies organisms for use in research.
Only authorized employees are allowed access to some laboratories in the resource centre.
These laboratories are protected by locked doors. Each door is controlled by a separate microprocessor. A digital camera is used to scan the iris of an employee who wishes to enter the lab. If the employee is authorized the doors are unlocked.
The company is planning to use a centralized computer system to secure the resource centre's building.
The operating system has an important role in this system.
Identify two functions of the operating system.
Compare a centrally controlled system with the system described above.
Outline the function of an output transducer.
Identify two benefits of using a digital camera as an input device in this control system.
Outline the use of a microprocessor in this control system.
Polling and interrupt are two operating system management techniques.
Suggest with reasons which of these two techniques is the most appropriate for this centrally controlled system.
A washing machine manufacturer has created its website to be viewed on standard desktop computers as well as mobile devices. The mobile browsing experience differs from desktop browsing.
Different devices such as desktop computers and mobile devices have different operating systems.
Define the term screen resolution.
Explain the role of the operating system (OS) in terms of managing the hardware resources.
Describe two issues resulting from the website being viewed on various devices, such as desktops and smartphones.
A washing machine uses a control system.
The microprocessor controls the washing machine and its actions. To complete the wash and rinse process the user selects the program, loads the washing machine and pushes the start button.
Describe the interaction between the sensors, microprocessors and output transducers in this situation.