Question
Which of the following best defines the concept of
Encapsulation in Object-Oriented Programming (OOP)?Solution
Encapsulation is one of the core principles of Object-Oriented Programming (OOP). It refers to the concept of bundling the data (attributes) and the methods (functions) that operate on the data into a single unit, or object, and restricting access to some of the object's components. This is typically achieved by using access modifiers such as private , protected , and public to control how the object's data can be accessed or modified. The key idea is to expose only the necessary functionalities (via public methods) while keeping the implementation details hidden.
- Why It Is Important: Encapsulation helps in hiding the complexity of the system and protects the integrity of the object’s state. By making attributes private and providing getter and setter methods, developers can control how the data is accessed or modified. This makes the software more modular, flexible, and easier to maintain, as changes to the internal implementation do not affect external components.
- Real-World Example: Consider a BankAccount class. The balance is encapsulated as a private attribute, and the methods to deposit or withdraw money are provided as public functions. This ensures that the balance cannot be directly changed, but can only be modified through the controlled deposit and withdrawal operations.
- Allowing objects to communicate with each other through function calls: This describes message passing or the process of communication between objects, but it is not encapsulation.
- The ability of an object to take on multiple forms: This is describing polymorphism , where an object can behave differently depending on its context.
- Organizing classes in a hierarchical manner: This refers to inheritance , where a class inherits properties and behaviors from another class.
- Storing related objects together in a single class: This does not necessarily describe encapsulation but could be referring to composition or aggregation , where objects are stored within other objects.
A cylindrical metal wire is reformed so that its length decreases by 20% with no change of volume. Its
resistance decreases by:
The density of the liquid when heated
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A mass m moves in a vertical circle of radius R under gravity. What is the minimum mechanical energy required to complete the circle?
Which of the following materials has the highest thermal conductivity?
One mole of any gas at standard temperature and pressure contains a volume of________?
Metalloids are
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