English Summer Holiday Homework 2017

Class –XII(A+B+C)

Q.1. Solve all the three set of class xii Board Examination held in the session 2016-17 in your notebook excluding the literature part which has not been taught till the break starts.

Q.2. Read the novel “Invisible Man” thoroughly and write the summary of the first half of the novel.

Q.3.(a) Write two articles in 200 Words on current problems prevalent in our society.

(b) Write two speeches on your choice subject to be delivered in morning assembly.

(c) Write two notices on organization of some events.

(d) Write an advertisement for “To Let’ column.

(e)Write an advertisement for “ Matrimonial column”.

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KV (AFS) UTTARLAI XII A CHEM

HOLIDAY H.W. FOR CLASS XII-A (CHEMISTRY) – B.K. YADAV.
(1) .write question and answers of 1 mark ,2mark ,3mark and 5 mark questions of last three years all indiacbse 12 board papers of chapter 1 and 2 of NCERT XII chemistry book.

(2) .Completion of project work.

XII B Subject : Chemistry

1.In some cases, it is found that a large number of colliding molecules have energy more than threshold value, yet the reaction is slow. Why?

2.In the determination of molar mass of A+B– using a colligative property, what may be the value of van't Hoff factor if the solute is 50% dissociated?

3.Which will have higher V.P., 0.1 M NaCl or 0.1 M BaCI2 solution in water? Why?

4.Why is Frenkel defect found in AgCl?

5.Explain why electrolysis of aqueous solution of NaCl gives H2 at cathode and Cl2 at anode.

6.Explain why the medicines are mixed with normal saline water (0.9% m/v aquous solution of NaCl) before being injected into the vien (I.V.).

7.For a first order reaction, it has 5 minutes for the initial concentration of 0.6 mol L–1 to become 0.4 mol L–1. How long will it take for the initial concentration to become0.3molL–1?

8.(A)Two liquid A and B boil at 145° C and 190° C respectively. Which of them has higher

vapour pressure at 80° C?

(B) Acetone (bp 329 K) and carbon disulphide (bp 320 K) are mixed in a definite composition so

that the mixture of two behaves like pure liquid and boils at 312 K. what name can be given to

such a mixture?

9. (i) 15 cm3 of liquid X and 20 cm3 of liquid Y are mixed at 20° C and the volume of solution was

measured to be 35.1 cm3. What is sin of Hmix?

(ii) Based on solute–solvent interactions arrange the following in order of increasing solubility in

n–octane and explain. Cyclohexane, KCl, CH3OH, CH3CN.

10.What is Van't Hoff factor in each of the following cases?

(a) Aq. K4[Fe(CN)6] which is 20% ionised(b) PCl5 which is 50% dissociated

(c) Benzoic acid which froms dimer to the extent of 50% in benzene

11.(i)Write down the name of crystal system having axial distance and axial angle

respectively . a ≠ b ≠ c and α = γ= 900 , β ≠ 900

(ii)Write down the name of crystal system having axial distance and axial angle respectively

a ≠ b ≠ c and α = β = 900 , γ = 1200

(iii)Write down name of crystal system present in CuSO4.5H2O.

12.(i) Name the Non–stoichiometric point defect which responsible for colour of alkali halides?

(ii) What is F–centre?

(iii) Mention one property which is caused due to the presence of F–centres in a solids

13. In the laclanche cell write the following :

(i) The chemical Equation involved at the cathode & anode.

(ii) Change in the oxidation state of Mn.

(iii) The complex entity formed between Zn2+(aq) and NH3(g)

14.(a)Explain why mercury cell is mainly used for low current devices like hearing aids, watches

camera, etc.?

(b) Predict the products of electrolysis in each of the following

(i) An aqueous solution of CuSO4 with copper electrodes.

(ii) An aqueous solution of CuSO4 with platinum electrode.

(iii) An aqueous solution CuCl2 with platinum electrodes.

(iv) Conc. solution of H2SO4 with platinum electrodes.

15. (a) For a reaction A + B Products, the rate law is : Rate = k [A] [B]-5/2.Find the unit of rate constant.

(b)What would be the effect on the rate of reaction due to the four-fold increase in a reactant

concentration, if the order of reaction were the following:

(i) Zero order (ii) First order (iii) 1/2 order (iv) Fourth order

(c)The rate constant for the reaction, is 3.0 x 10-5 s-l. If the rate is 2.40 x 10-5mol L-l s-l, then

calculate the initial concentration of N2O5(in mol L-l).

Holiday home (summer vacation)work for class XII (PHYSICS) Date 03-05-2017

UNIT I

(1) Draw an equipotential surface for a system, consisting of two charges Q,-Q separated by a distance ‘r’ in air.

(2) Obtain the expression for the potential energy of an electric dipole of dipole moment p placed in an electric field E.

(3) (a) Derive an expression for the energy stored in a parallel plate capacitor C, charge to a potential difference V.

(b) Obtain the equivalent capacitance of the network given below. For a supply 300 V, determine the charge and voltage across C4.

(4) Define the term ‘potential energy’ of charge ‘q’ at a distance ‘r’ in an external electric field.

(5) Define electric flux. Write its S.I. unit.A charge q is enclosed by a spherical surface of radius R. If the radius is reduced to half, how would the electric flux through the surface change?

(6) Draw three equipotential surfaces corresponding to a field that uniformly increases in magnitude but remains constant along Z-direction. How are these surfaces different from that of a constant electric field along Z-direction?

(7) A positive charge (+q) is kept in the vicinity of an uncharged conducting plate. Sketch electric field lines originating from the point on to the surface of the plate.Drive the expression for the electric field at the surface of a charged conductor.

(8)A parallel plate capacitor is charged by a battery. After some time the battery is disconnected and a dielectric slab of dielectric constant K is inserted between the plates. How would (i) the capacitance, (ii) the electric field between the plates and (iii) the energy stored in the capacitor, be affected? Justify your answer.

(9) Name the physical quantity whose S.I. unit is J/C. Is it scalar or a vector quantity?

(10) A spherical conducting shell of inner radius r1 and outer radius r2 has a charge Q. A charge q is placed at the centre of the shell.

(a) What is the surface charge density on the (i) inner surface, (ii) outer surface of the shell?

(b) Write the expression for the electric field at a point x > r2 from the centre of the shell.

(11) Show that the electric field at the surface of a charged conductor is given by E =σ/ϵ0 n^ where σ is the surface charge density and n^ is a unit vector normal to the surface in the outward direction.

(12) A hollow metal sphere of radius 10 cm is charged such that the potential on its surface is 5 V. What is the potential at the centre of the sphere?

(13) Net capacitance of three identical capacitors in series is 2 µF. What will be their net capacitance if connected in parallel?Find the ratio of energy stored in the two configurations if they are both connected to the same source?

(14) Plot a graph showing the variation of coulomb force (F) versus (1/r2) , where r is the distance between the two charges of each pair of charges : (1µC, 2 µC ) and (2µC, -3 µC) . Interpret the graphs obtained .

(15) A thin straight infinitely long conducting wire having charge density λ is enclosed by a cylindrical surface of radius r and length l, its axis coinciding with the length of the wire . Find the expression for the electric flux through the surface of the cylinder.

(16) A charge q is placed at the centre of a cube of side l. What is the electric flux passing trough two opposite faces of the cube?

(17)A test charge q is moved without acceleration from A to C along the path from A to B and then from B to C in electric field E as shown in the figure. (i) Calculate the potential difference between A and C. (ii) At which point (of the two) is the electric potential more and why?

(18)An electric dipole is held in a uniform electric field. (i) Show that the net force acting on it is zero (ii) The dipole is aligned parallel to the field. Find the work done in rotating it through1800.

(19)Deduce the expression for the electrostatic energy stored in a capacitor of capacitance C and having charge Q. How will the (i) energy stored and (ii) the electric field inside the capacitor be affected when it is completely filled with a dielectric material of dielectric constant K?

(20)Two charges of magnitudes -3Q and +2Q are located at points (a,0) and (4a,0) respectively. What is the electric flux due to these charges through a sphere of radius ‘5a’ with its centre at the origin?

(21) A slab of material of dielectric constant Khas the same area as the plates of a parallel-plate capacitor but has a thickness d/3, where dis the separation between the plates. Find out the expression for its capacitance when the slab is inserted between the plates of the capacitor. (22) (a) Define electric dipole moment. Is it scalar or a vector? Derive the expression for the electric field of a dipole at a point on the equatorial plane of the dipole.

(b) Draw the equipotential surfaces due to an electric dipole. Locate the points where the potential due to the dipole is zero.

(23)Using Gauss’s laws deduce the expression for the electric field due to a uniformly charged spherical conducting shell of radius R at a point (i) outside and (ii) inside the shell.Plot a graph showing variation of electric field as a function of r >R andr < R .( r being the distance from the centre of the shell)

(24) Two charged sphere are repelled by force F .How the force between them is changed if a plastic sheet is introduced between them?

(25) A capacitor is having capacitance C and energy stored is U. Now it is connected with an uncharged capacitor of same capacitance. Find out the ratio of energy stored before connecting and after connecting.

UNIT II

(1). Two conducting wires X and Y of same diameter but different materials are joined in series across a battery. If the number density of electrons in X is twice that in Y, find the ratio of drift velocity of electrons in the two wires. (2). Write any two factors on which internal resistance of a cell depends. The reading on a high resistance voltmeter, when a cell is connected across it, is 2.2 V. When the terminals of the cell are also connected to a resistance of 5 as shown in the circuit, the voltmeter reading drops to 1.8 V. Find the internal resistance of the cell. (3). State Kirchhoff’s rules. Use these rules to derive balance condition of Wheatstone bridge. (4). Two heating elements of resistances R1 and R2 when operated at a constant supply of voltage, V, consume powers P1 and P2 respectively. Deduce the expressions for the power of their combination when they are, in turn, connected in (i) series and (ii) parallel across the same voltage supply. (5) Two wires of equal length, one of copper and the other of manganin have the same resistance. Which wire is thicker?(6)Define relaxation time of the free electrons drifting in a conductor. How is it related to the drift velocity of electrons? Use this relation to deduce the expression for the electrical resistivity of the material. (7) Draw the variation of resistivity of conductors , semiconductors and alloys with temperature. (8) Find out an expression for drift velocity. (9) Draw circuit diagram for measurement of unknown resistance using metre bridge. (10) What are the factors on which resistance of a conductors depends?

HOLIDAY HOMEWORK CLASS 12THA, B, C MATHEMATICS

  1. If and are equivalence relations in a set A, show that is also an equivalence relation.
  2. Show that the function defined by , is one- one and onto function
  3. Let be defined as if is odd andif is even. Show that is invertible. Find the inverse of . Here, is the set of whole numbers.
  4. is defined by ,.
  5. Show that the relation R in the set ,given by

is a multiple of is an equivalence relation. Also find the set of all elements related to 1.

  1. Let be a function defined by .Show that is iinvertible, where is the range of . Hence find
  2. Consider given by .Show that is invertible .Hence find
  3. Given a non- empty set X, consider the binary operation on given by

, where is the powewr set of .Show that is the identity element and is the only invrtible element in with with respect to operation .

  1. Let R be a relation on the set A , where N is the set of natural numbers, defined by if and only if Show that R is an equivalence relation.
  2. Show that the relation R in the set , defined by iff , is an equivalence relation.
  3. On the set , a binary operation is defined as :

Write the operation table of the operation and prove that zero is the identity for

this operation and each element of the set is invertible with being the

inverseof .

  1. Write the principal value of :- 4 (1) + .
  2. Write the value of :- tan ( 2) .
  3. Evaluate: .
  4. .
  5. Solve for .
  6. Prove that : .
  7. Solve for .
  8. Draw arrow diagrams for the following functions with examples:

(i)one-one

(ii)many

(iii)into

(iv) onto

(iv)bijective .

  1. Draw graphs for :

(i)

(ii)

(iii)

  1. To raise money for orphanage, students of three schools , and organized an exhibition in their locality, where they sold paper bags, scrap-books and pastel sheets made by them using recycled paper, at the rate of Rs., Rs.and Rs.per unit respectively. School sold paper- bags,scrap-books and pastel sheets.School sold paper - bags,scrap-books and pastel sheets while School sold paper - bags,scrap-books and pastel sheets .Using matrices, find the total amount raised by each school.By such exhibition, which values are inculcated in the students?
  2. If ,then find the value of .
  3. Express the matrix as the sum of a symmetric and a skew symmetric matrix.
  4. If , then find the matrix .
  5. If , find ,using elementary row transformations.
  1. If find satisfying when where is transpose of .
  1. Let then show that . Using this result calculate .
  2. There are families , and . The number of men, women and children in these families are as under :

Men / Women / Children
Family / / /
Family / / /
Family / / /

Daily expenses of men, women and children are Rs. , Rs. and Rs.

respectively. Only men and women earn and children do not. Using matrix

multiplication, calculate the daily expenses of each family. What impact does more

children in the family create on the society?

  1. A typist charges Rs.for typing English and Hindi pages, while charges for typing English and Hindi pages are Rs.. Using matrices, find the charges of typing one English and one Hindi page separately. However typist charged only Rs per page from a poor student Shyam for Hindi pages. How much less was charged from this poor boy? What values are reflected in this problem ?

Subject : Computer ScienceClass XII A

  1. Predict the output based on the following (Any 10)

(i)Random Function

(ii)Call by value and call by reference

(iii)String Convert

  1. Define the class with given specification ( any 10)
  2. What is access specifiers? Explain using examples?
  3. Practical work : Write the program related to class and object (any 05)

Subject : Informatics PracticesClass XII C

  1. Named the different swing controls with their properties and method .
  2. Define the different inbuilt methods in NetBeans JAVA.
  3. Explain the control structure in Netbean JAVA with suitable examples.
  4. Develop GUI application based on swing control and calculate (Choose your own criteria)

i)Discount calculator

ii)Commission calculator

iii)Grade calculator

iv)Simple interest

v)Total wedges

Holiday Home-Work

ECONOMICS

Q1. Explain central problems.

Q2. Explain consumer equilibrium in ordinal approach.

Q3. Explain concept of PPC.

Q4. State Law of DMU.

Q5. Explain properties of IC.

Business Studies

Project – Based On Henri Fayol’s Principles.

Accountancy.

Project – Comprehensive Project
Minimum 28 transaction, Journal, ledger, Trial Balance, 5 adjustments, and Final Accounts.
There must be balance of Debtors, Creditors and Loan accounts in final accounts.
There will be no adjustments entries in transactions
Chapter – Fundamental of partnership
Chapter – Goodwill
Chapter – Admission of partner
Chapter – Retirement of Partner
Chapter – Dissolution of Partnership firm
(Questions which we have solved in the class room)