1. What is the result of the expression 2 + "2"?
Explanation: JavaScript performs type coercion and converts the number 2 to a string before concatenating it with "2."
Report for correction2. What will be the result of the following code , console.log(5 + "5");?
Explanation: JavaScript performs type coercion, so it converts the number 5 to a string and concatenates it with the string "5."
Report for correction3. What does the typeof operator return for an undefined variable?
Explanation: The typeof operator returns "undefined" for an undefined variable.
Report for correction4. How do you comment a single line of code in JavaScript?
Explanation: In JavaScript, a single-line comment is created using "//."
Report for correction5. Which of the following is the correct way to write a JavaScript array?
Explanation: The correct way to write a JavaScript array is to use square brackets and separate elements with commas.
Report for correction [1, 2, 3, 4]
{1, 2, 3, 4}
(1, 2, 3, 4)
1, 2, 3, 4
6. Which operator is used to compare two values for equality without considering their data types?
Explanation: The double equals (==) operator is used for loose equality comparison.
Report for correction7. Which operator is used for strict equality comparison in JavaScript?
Explanation: The triple equals (===) operator is used for strict equality comparison, which checks both value and data type.
Report for correction8. What is an anonymous function in JavaScript?
Explanation: An anonymous function is a function with no name.
Report for correction9. What does the localStorage object in JavaScript allow you to do?
Explanation: The localStorage object in JavaScript allows you to store key-value pairs in the user's web browser.
Report for correction10. What does JavaScript primarily allow you to do in web development?
Explanation: JavaScript is primarily used to add interactivity and behavior to web pages, making them dynamic.
Report for correction11. Which built-in object is used to display messages in a pop-up box in JavaScript?
Explanation: The alert method is used to display messages in a pop-up box in JavaScript.
Report for correction12. How do you check the length of an array in JavaScript?
Explanation: To check the length of an array in JavaScript, you use the "length" property.
Report for correction13. Which of the following is NOT a valid JavaScript data type?
Explanation: JavaScript does not have a data type called "Character." Instead, characters are represented as strings.
Report for correction14. Which of the following statements is used to exit a loop prematurely in JavaScript?
Explanation: The "break" statement is used to exit a loop prematurely in JavaScript.
Report for correction15. What is the result of the expression 5 > 3 && 2 < 4?
Explanation: The && operator returns true if both conditions are true, which is the case here.
Report for correction16. What does the NaN value represent in JavaScript?
Explanation: NaN stands for "Not a Number" and represents an unrepresentable value in JavaScript.
Report for correction17. Which function is used to remove an item from the end of an array in JavaScript?
Explanation: The pop() function is used to remove an item from the end of an array in JavaScript.
Report for correction18. How can you convert a string to an integer in JavaScript?
Explanation: You can use the parseInt() function to convert a string to an integer in JavaScript.
Report for correction19. What does the this keyword refer to in JavaScript?
Explanation: In JavaScript, the this keyword refers to the current function or context.
Report for correction20. What is the purpose of the else statement in JavaScript?
Explanation: The else statement is used to specify an alternative condition to be executed if the initial condition is false.
Report for correction21. What is the purpose of the setTimeout() function in JavaScript?
Explanation: The setTimeout() function is used to delay the execution of a function by a specified number of milliseconds.
Report for correction22. What is the purpose of the forEach method in JavaScript?
Explanation: The forEach method is used to loop through the elements of an array and perform a specified action for each element.
Report for correction23. Which statement is used to throw an exception in JavaScript?
Explanation: The throw statement is used to throw an exception in JavaScript.
Report for correction24. Which keyword is used to declare a variable in JavaScript?
Explanation: The "var" keyword is used to declare variables in JavaScript.
Report for correction25. What is the correct way to declare a function in JavaScript?
Explanation: The correct way to declare a function in JavaScript is to use the "var" keyword followed by the function name and its definition.
Report for correction