All questions

• In a compound C, H and N atoms are present in 9 : 1 : 3.5 by weight . Answer: C₆H₈N₂ Divide each mass by the atomic mass to get the mole ratio: C: 9/12 = 0.75 H: 1/1 = 1 N: 3.5/14 = 0.25 Dividing by the smalles... Some Basic Concepts of Chemistry 1 answer
• With increase of temperature, which of these changes? JEE Option C is correct molarity Temperature has no effect on mass but it has significant effect on volumes. Hence molality, mole fraction, mass... Some Basic Concepts of Chemistry 1 answer
• If both FeX2 & FeY3 are found to exist, X & Y can be : (1) X = F, Cl, Br, I Y = F, Cl, Br (2) X = Cl, Br, (1) X = F, Cl, Br, I :: Y = F, Cl, Br is the correct option Explaination:: FeI₃ does not exist as I^(–) reduces Fe³⁺ to Fe²⁺. 2Fe³⁺ + 2I – →... Some Basic Concepts of Chemistry 1 answer
• The period of oscillation of a simple pendulum is T = 2π\sqrt{Lg}. Measured value of 'L' is 1.0 m from meter Answer: (1) 1.13% Step 1: Write g in terms of the measured quantities. T = 2π√(L/g) ⇒ g = frac4π²LT² Step 2: Relative error. For a product o... Physics 1 answer
• WAP in C++ that first initializes an array of given 10- sorted real numbers. The program must verify whether a given Output:: Below code is executed on gdb turbo c++ compiler , it takes 10 input of given number then sort by binary search technique #include<... Programming 2 answers
• write html code for following Faculty Arts Science Commerce Code :: <!DOCTYPE html> <table border="1" cellspacing="10px"> <tr> <th rowspan="2" colspan="2" > </th> <th colspan="3"> Faculty</th> </tr> <... HTML 1 answer
• JEE MAINS EXAM APRIL AND MAY SESSION DATES JEE MAINS EXAM APRIL AND MAY SESSION DATES https://jeemain.nta.nic.in/webinfo2021/Page/Page?PageId=1&LangId=P May attempt is postponed Uncategorized 1 answer
• The least value of |z| where z is complex number which satisfies the inequality Answer: (1) 3 Read the inequality as exp((|z|+3)(|z|-1)/|z|+1log_e 2) ≥ log_(sqrt2)|5sqrt7 + 9i| . Right side: |5sqrt7 + 9i| = √(175 + 81) =... COMPLEX NUMBERS AND QUADRATIC EQUATIONS 1 answer
• The area of the triangle with vertices A(z), B(iz) and C (z + iz) is : Answer: (2) 1/2|z|² Look at the sides meeting at C: overrightarrowCA = z - (z + iz) = -iz , length |z| . overrightarrowCB = iz - (z + iz) =... COMPLEX NUMBERS AND QUADRATIC EQUATIONS 1 answer
• Let S1, S2 and S3 be three sets defined as S1 = {z ∈ C : |z - 1| ≤ √2} Answer: (3) Has infinitely many elements Let z = x + iy . S₁ : |z-1| ≤ sqrt2 is the closed disc with centre (1, 0) and radius sqrt2 . S₂ : (... COMPLEX NUMBERS AND QUADRATIC EQUATIONS 1 answer
• If the equation a|z|^2 + bar (bar α z + α bar z) + d = 0 represents a circle Have a look in image for answer COMPLEX NUMBERS AND QUADRATIC EQUATIONS 2 answers
• Let a complex number be w = 1 – √3i . Let another complex number z be such that |zw| = 1 and arg(z) – arg(w) Correct Answer is (2) 1/2 Explaination:: Image:: COMPLEX NUMBERS AND QUADRATIC EQUATIONS 1 answer
• The statement among the following that is a tautology is : (1) A ∧ (A ∧ B) (2) A ∧(A ∧ B) (3) B → [A ∧(A → B)] (4) [A ∧ (A → B)] → B Correct Answer is (4) [A ∧ (A → B)] → B MATHEMATICAL REASONING 2 answers
• The negation of the statement ∼p∧(p∨q) is : A ) p∨∼q B) ∼p∨q C) ∼ p ∧ q D) p ∧ ∼ q Option (A) is correct A ) p∨∼q MATHEMATICAL REASONING 2 answers
• The statement A → (B → A) is equivalent to : (1) A → (A ∧ B) (2) A →(A → B) (3) A → Option 4) is correct (4) A → (A V B) MATHEMATICAL REASONING 2 answers
• The contrapositive of the statement "If you will work, you will earn money" is : (1) You will earn money, Correct answer is (3) If you will not earn money, you will not work Contrapositive of p → q is ~q → ~p p : you will work q : you will earn m... MATHEMATICAL REASONING 1 answer
• Let F1(A,B,C) = (A∧~B) ∨ [~C ∧ (A ∨ B)] ∨~A and F2(A, B) = (A ∨ B) ∨ (B →~A) be two logical expressions. Correct option is (3) (3) F₁ is not tautology but F₂ is a tautology F₁ : (A ∧~B) ∨[~C ∧ (A ∨ B)] ∨~A F₂ : (A ∨ B) ∨ (B →~A) F₁ : (A ∧~B) ∨~A... MATHEMATICAL REASONING 1 answer
• Which of the following Boolean expression is a tautology? (1) (p ∧ q) ∨ (p ∨ q) Correct Answer is 4) (p ∧ q) → (p → q) MATHEMATICAL REASONING 1 answer
• If the Boolean expression (p ⇒ q) ⇔ (q * ( ∼ q) is a tautology, then the boolean expression p * ( ∼ q) is equivalent to : Answer: (a) (p → q) ⇔ (q * ~ P) p q p → q q * ~ P ~ q ~ q ∧ p ~ (~ q ∧ p) T T T T F F T T F F F T T F F T T T F F T F F T T T F T ∴ ~ (~ q ∧... MATHEMATICAL REASONING 1 answer
• If the Boolean expression ( p ∧ q ) ⊙ ( p ⊗ q ) is a tautology, then ⊙ and ⊗ are respectively given by : Option 1 is Correct ( →, →) ( p ∧ q ) → ( p → q ) ( p ∧ q ) → ( ∼ p ∨ q ) ( ∼ p ∨ ∼ q ) ∨ ( ∼ p ∨ q ) ∼ p ∨ ( ∼ q ∨ q ) ⇒ Tautology ⇒ ⊙ ⇒→ ⊗... MATHEMATICAL REASONING 1 answer
• If P and Q are two statements, then which of the following compound statement is a tautology ? Answer: (b) (P ⇒ Q) ^ ~ Q = (~ P ∨ Q) ^ ~ Q ≡ (~ P ∧ ~ Q) ∨ (Q ∧ ~ Q) = (~ P ∨ ~ Q) ∨ (Q ^ ~ Q) = ~ (P ∨ Q) Now, (1) ~ (P v Q) ⇒ P = (P v Q)... MATHEMATICAL REASONING 1 answer
• Let Z be the set of integers. If A = {x ∈ Z : 2(x +2)(x^2 - 5x + 6) = 1} and B {x ∈ Z : -3 < 2x - 1 < 9}, Option 2) 215 is correct SETS, RELATIONS AND FUNCTIONS 2 answers
• Let S = {1, 2, 3, ... , 100}. The number of non-empty subsets A of S such that the product of elements in A is even is : The correct option (2) 2⁵⁰(2⁵⁰ – 1) Explanation: Product of elements in A is even = (total subjects) – (Number of subject of all whose eleme... SETS, RELATIONS AND FUNCTIONS 1 answer
• Let X = {n ∈ N : 1 ≤ n ≤ 50}. If A = {n ∈ X : n is multiple of 2} and B = {n ∈ X : n is a multiple of 7}, n(A) = 25 n(B) = 7 n(A ∩ B) = 3 n(A ∪ B) = 25 + 7 - 3 = 29 SETS, RELATIONS AND FUNCTIONS 2 answers