Jay's Mathematics Classes

 ELECTRIC CHARGES AND FIELDS   BASIC PROPERTIES OF ELECTRIC CHARGE  If the sizes of charged bodies are very small as compared to the distances between them, we treat them as point charges. All the charge content of the body is assumed to be concentrated at one point in space Additivity of charges Charge is conserved  Quantisation of charge 1. Additivity of charges If a system contains n charges `q_1 , q_2 , q_3 , …, q_n` , then the total charge of the system is `q_1 + q_2 + q_3 + … + q_n`  .  2. Charge is conserved Within an isolated system consisting of many charged bodies, due to interactions among the bodies, charges may get redistributed but it is found that the total charge of the isolated system is always conserved. Conservation of charge has been established experimentally.  3. Quantisation of charge Experimentally it is established that all free charges are integral multiples of a basic unit of charge denoted by e. Thus charge q on a bo...

 Determinant ➤ If `M` is the set of square matrices, `K` is the set of numbers (real or complex), and `f : M → K` is defined by `f (A) = k`, where `A ∈ M` and `k ∈ K`, then `f(A)` is called the determinant of `A`. It is also denoted by `| A|` or det `A` or `∆`. Remarks  (i) For matrix `A, | A|` is read as the determinant of `A` and not modulus of `A`.  (ii) Only square matrices have determinants.

 📝Chemistry Class 12 Questions Multiple Choice Questions  1. The number of atoms in a body-centered cubic (bcc) unit cell of a monoatomic elementary substance is equal to (A) 1  (B) 2 (C) 3  (D) 4 Ans: (B) 2. Molarity of an aqueous solution containing  40g of `NaOH` in two litre of solution is (A) 0.5  (B) 1.0 (C) 1.5  (D) 0.75 Ans: (A) 3.   `2CH_3Br + 2Na overset{dry  ether}{rightarrow} CH_3-CH_3 + 2NaBr` The reaction is : (A) Friedel crafts reaction (B) Wurtz reaction (C) Fittig reaction (D) Wurtz Fittig reaction Ans: (B) 4. When aqueous solution of `NaCl` is electrolysed the product obtained at cathode is (A) Hydrogen  (B) Sodium metal (C) Oxygen  (D) Chlorine Ans: (A) 5. Which of the following is ore of iron (A) Haematite  (B) Cassiterite (C) Dolomite  (D) Bauxite Ans: (A) 6. The most stable hydride of group 15 elements is (A) `NH_3`  (B) `PH_3` (C) `AsH_3`  (D) `SbH_3` Ans: (A) 7. Which ...

📝 Mathematics Class 12 Questions  Multiple Choice Questions  1. Let `R` be a relation on N defined by `x + 2y = 8.`The domain of `R` is a) {2, 4, 6} b) {1, 2, 3, 4} c) {2, 4, 6, 8} d) {2, 4, 8} Ans: (c) 2. Let `L` be the set of all lines in a plane and `R` be the relation in `L` defined as then is `R = {(L_1, L_2):L_1` is perpendicular to `L_2}` (a) reflexive and transitive (b) symmetric but neither reflexive nor transitive (c) symmetric and transitive (d) none of these. Ans: (b)

 📝Accountancy Class 12 Questions  Multiple Choice Questions  1. Partnership agreement can be  (a)  Oral (b) Written (c)Oral or Written (d) None of these Ans:(c)  2. In the absence of a partnership deed profits and losses are shared (a)  Equally (b) In the ratio of capitals (c) As per the agreement (d) All of these Ans: (a) 3. In the absence of a partnership deed, partners are not entitled to receive (a)  Salaries (b)  Commission (c)  Interest on capital (d)  All of these Ans: (c) 4. Revaluation account or Profit and Loss adjustment account is (a) Personal Account (b) Nominal Account (c) Real Account (d) None of these Ans: (b) 5.  A, B, C, and D are partners sharing their profits and losses equally. They change their profit sharing ratio to 2:2:1:1. How much will C sacrifice (a) 1/6 (b) 1/12 (c) 1/24 (d) None of these Ans: (b) 6. Excess of Average Profit over the Normal Profit is called (a) Superprofit ...

 Question Bank Class 12 Mathematics  Chapters  ● Matrices 📝 ●  Sample Questions 2021 - 2022 📝

  Theory of Consumer Behaviour In this chapter, we will study the behaviour of an individual consumer. The consumer has to decide how to spend her income on different goods.  Economists call this the problem of choice.  Most naturally, any consumer will want to get a combination of goods that gives her maximum satisfaction. What will be this ‘best’ combination? This depends on the likes of the consumer and what the consumer can afford to buy. The ‘likes’ of the consumer are also called ‘preferences’. And what the consumer can afford to buy, depends on the prices of the goods and the income of the consumer. Consumer's Affordability  = f( income, price), `\forall` income , price `\in \R_+` This chapter presents two different approaches that explain consumer behaviour ( i) Cardinal Utility Analysis and (ii) Ordinal Utility Analysis. Preliminary Notations and Assumptions A consumer, in general, consumes many goods; but for simplicity, we shall consider t...

 Accounting for Not-for-Profit Organisation Back Introduction  There are certain organisations that are set up for providing service to their members and the public in general. Such organisations include clubs, charitable institutions, schools, religious or ganisations, trade unions, welfare societies, and societies for the promotion of art and culture. These organisations have service as the main objective and not the profit as is the case of organisations in the business. Normally, these organisations do not undertake any business activity and are managed by trustees who are fully accountable to their members and the society for the utilization of the funds raised for meeting the objectives of the organisation. Hence, they also have to maintain proper accounts and prepare the financial statement which takes the form of Receipt and Payment Account; Income and Expenditure Account; and Balance Sheet. at the end of every accounting period (normally a financial year). Meaning a...