Question Discussion & Solution

Rajendra Prasad is the first president of India. Similarly, the first president of USA is George Washington.

Hence, George Washington is the correct answer.

Concept

The javac command in Java compiles a program from a command prompt.

It reads a Java source program from a text file and creates a compiled Java class file.

Syntax

javac filename [options]

For example, to compile a program named Abc.java, use this command:

javac Abc.java

Total number of boxes of matchsticks = 3600

Total number of cartons = 10

Let the number of packets in one carton be x.

⇒ Number of packets in 10 cartons = 10x.

Number of boxes of matchstick in a packet = 30

⇒ Number of boxes of matchstick in 10x packets = 30(10x) = 300x

So, we have:

Total number of boxes = Number of boxes of matchstick in 10x packets

⇒ 300x = 3600

⇒ x = 12

A scalar is a quantity which has only a magnitude but not a direction whereas vector is a quantity which has both a magnitude and a direction.

Volume is a scalar quantity similarly, momentum is a vector quantity while time, speed and energy are the scalar quantities.

A constructor is a member function of a class that initializes objects of a class. In C++, Constructor is automatically called when an object (instance of a class) creates. It is a special member function of the class.

Syntax

class_name(parameter1, parameter2, ...)

{

    // constructor Definition

}

Default Constructor

It is the constructor that doesn’t take any argument. It has no parameters.

Parameterized Constructors

It is possible to pass arguments to constructors. Typically, these arguments help initialize an object when it is created. 

Copy Constructor

A copy constructor is a member function that initializes an object using another object of the same class.