CLASS VIII CHAPTER NAME : ENHANCING CALCULATOR

Multiple Choice Questions

1     1. Which mechanism allows one class to inherit the properties of another class ?

a.            Function                             b.           Function Overloading  

c.            Inheritance                         d.           Exception Handling

2     2. Which keyword is used to inherit a class ?

a.            super                                  b.           extends

c.            class                                   d.           void

3     3. Which one of the following options is also called a derived class ?

a.                   sub                                       b.            super 

c.           parent                                  d.            base

4     4. Which one of the following options is used to call the function of the base class in the derived
           class ?

a.                  parent                                  b.           derived

c.           extends                               d.            super                     

5     5. Which one of the following options should be different to overload functions ?

a.          Function name                    b.           Function parameter list

c.          Function return type           d.           Function call

True or False :-

11.  A function cannot have the same name and different parameters.         FALSE

22.  A base class can also be called a parent class.            TRUE

33.  To overload functions, parameters should be different but the name should be the same.    TRUE

44.  A derived class cannot be called as a child class.       FALSE

55.  The extends keyword is used to call the function of a base class in a derived class.            FALSE

Subjective Qustions :-

Qus. - 01 : What is inheritance ?

Ans. :- Inheritance is a mechanism that allows a class to inherit properties of another class.

Qus. - 02 : What is the difference between the extends and super keywords ?

Qus. - 03 : What are the derived and base classes ? Explain in detail.

Ans. :- Derived class :- The class that inherits property of another class is called the derived class. A derived class is also known as the Child class or the Sub class.
Base Class :- The class that gets inherited is called the base class. A base class is also known as the Parent class or the Super class.

Qus. - 04 : What is function overloading ?

Ans. :- Function overloading :- The process of functions having the same name but different parameters is known as Function overloading.

Qus. - 05 : What is a parameter ?

Ans. :- The variables declared within the brackets of a function are known as parameters.

Lab Question :

Qus. - 01 : Write a program to display the menu to order a burger at a burger point. Write another class that contains information on beverages. The beverages class must be inherited by the burger class.

Ans:

Qus. - 02 : Write a program to  find the area of square and triangle using function overloading.
Ans :-
class FunctionOverloading 
{
 public static void main(String args[]) 
{
   FunctionOverloading fo = new FunctionOverloading();
   fo.area(5);
   fo.area(11,12);
    }
 void area(float s)
    {
        System.out.println("The area of Square is " + (s*s));
    }
 void area(float b, float h)
    {
        System.out.println("The area of the Triangle is " + (b*h)/2);
    }
}

Qus. - 03 : Write a program to use inheritance and function overloading.

Ans. :- 
class FunctionOverloading
{
void area(float s)
    {
     System.out.println("The area of Square is " + (s*s));
    }
 void area(float b, float h)
    {
System.out.println("The area of the Triangle is " + (b*h)/2);
    }
}
class Inheritance extends FunctionOverloading
{
 public static void main(String args[])
{
Inheritance i = new Inheritance();
i.area(5);
i.area(11,12);
    }
}