Dashain Vacation Home Assignment-2069
Grade XI, Science

Note: Home assignments of each subject should be done in different copies/papers.

English 1. Write an essay on ‘Dashain and its significance in Hindu Religion’. 2. Prepare a report on ‘Global Warming, its consequences and solutions’. 3. Write an article on ‘Importance of Media’. 4. Write on ‘English for Global education’.
Mathematics
1. Find the angle between the pair of straight lines x2 -2secAxy +y2= 0.
2. Evaluate: limx→∞ 3x2-2x+5x3
3. Prove that: A-B=B-A
4. Define lower triangular matrix with an example.
5. Find the equation of circle concentric with the circle x2+ y2 – 6x + 12y + 15 = 0 and having the area twice the area of the given circle.
6. For any two real numbers x and y, prove that |x+y| ≤ |x| + |y|.
7. What do you mean by tautology of compound statement? Give an example of it.
8. For any positive constant ‘a’ and for any real number ‘x’ , prove that |x| < a ⇒ -a < x < a.
10. Prove that the tangent to the circle x2+y2=5 at the point (1,-2) also touches the circle x2 + y2 - 8x + 6y + 20 = 0 and find the point of contact.
11. If P is the length of perpendicular dropped from the origin of the line xa + yb = 1 prove that 1a2 + 1b2 = 1 p2.
12. Find the equation of the circle with centre at (4, -1) and passing through the origin.
13. Evaluate; limx→osin⁡(x-a)x-a
14. Define absolute value of a real number. Rewrite the following relation without using absolute value sign2x-1≤5. Also draw the graph of the inequality.
15. Prove that x2+1xyxzxyy2+1yzxzyzz2+1 = 1 + x2+y2+z2
16. Solve the following system by using row-equivalent matrix method and inverse matrix method. 3x + y + 2z = 1, 2x + 3y + z = 5, x + 2y – z = 8
17. Evaluate: limh→0 sinx+h - sinxh
18. If A= 1321, find x and y such that A2- xA-yI=0 where I and 0 are unit and null matrices respectively.
19. Evaluate: limx→θxcosθ+θcosxx-θ
20.Define removable discontinuity at x=a. Also show that the following function has a removable discontinuity at x=2. f(x) = 2-x2for x<22 for x=2x-4 for x>2
21. Find the angle between two straight line whose equation are y=m1x+c1 and y=m2x+c2. Also find the conditions under which the two straight lines will be: i) Parallel ii) Perpendicular.
22. Prove that the straight lines joining the origin to the point of intersection of the line xa + yb = 1 and the curve x2 + y2 = c2 are at right angles if 1a2 + 1b2 = 1c2
23. P and Q are two points on the line x-y+1=0 and are at a distance of 5 units from the origin. Find the area of the triangle OPQ.
24. Show that the lines joining the origin to the points common to x2 + hxy - y2 + gx + fy = 0 and fx – gy = k are at right angles for all values of k≠0.
25. If nU=300, nA= 250, nB= 150, find i) the maximum and minimum values of n(A∪B) II) the maximum and minimum values of n(A∩B).
Chemistry
1. State and explain Dalton’s law of partial pressure. A flask of 0.3 litre capacity was weighed after it had been evacuated. It was then filled with a gas of unknown molecular mass at 1.0 atm pressure and the temperature of 300k. The increase in the mass of the flask was 0.977 gm. Calculate the molecular mass of the gas. 2. What are the basic assumptions of Bohr’s atomic model? 3. Describe the manufacture of nitric acid from catalytic oxidation of ammonia. 4. State Boyle’s law and Charles’ law. Derive PV=nRT. 5. How is ammonia manufactured by Haber’s process? Write its action upon
i) Nessler’s reagent ii) Excess chlorine iii) hot copper oxide 6. Write short notes on a. Bohr’s explanation of hydrogen spectrum b. Detection of Nitrogen as foreign element in organic compound c. Law of reciprocal proportions d. Kinetic theory of gases e. Bohr’s atomic model f. Differences between organic and inorganic compounds g. Ozone layer depletion and ozone hole 7. How is nitrogen detected in an organic compound as a foreign element? 8. What are the basic assumptions of electronic theory of valency? 9. State and explain Graham’s law of diffusion. a) The rate of diffusion of a saturated hydrocarbons (CnH2n+2) gas is 1.033 times that of O2 gas under similar conditions. Find the molecular mass and the value of ‘n’ for the gas. b) How many moles of O2 must be added to a mixture of 2.8 gm of CO and 3.2 gram of SO2 present in 7 liters flask at 25oC to bring the total pressure to 1.5 atm? 10. Describe the manufacture of nitric acid by Ostwald’s process. Write the action of i) Conc. HNO3 with iodine ii) Dilute HNO3 with Mn iii) Cold and conc. HNO3 with Fe 11. How Ozone is prepared in laboratory? Write its action on a) PbS b) HCl c) acidified K2MnO4 d) K4[Fe(CN)6] e) P4 12. State and explain Law of reciprocal proportion. 13. State and explain Law of multiple proportions. 14. State and explain Law of definite proportion. 15. Write a short note on Position of Hydrogen in periodic table. Physics
Short Questions 1. What types of experimental data are most reliable? Describe in terms of precession and accuracy. 2. What is the angle between two vectors A and B for the cross product A.B = 0? 3. You throw a stone along-side of a river with velocity 20 m/s at an angle 40o that makes just cross the river. Is there another angle to achieve the same range? 4. A body covered a distance of 1 m along a semicircular path. What will be the magnitude of displacement of the body and what will be the ratio of distance to displacement? 5. If A.B = C.A, is it necessary that B = C? 6. Telephone wires become taut in winter and slag in summer, why? 7. Tea cools faster in cold days than the summer days, why? 8. It takes more time to evaporate the same mass of water than to melt the ice by supplying same amount of heat, why? 9. Sky appears circular when observed from water, why? 10. A mirror is kept on a wall. How do you recognize that whether the mirror is concave, convex or plane without touching it? 11. Why does a plastic comb become charge when it is rubbed with another body? 12. The charge stored on a capacitor is doubled. What happens to its capacitance?
Long questions 1. Derive the dimensional relation of velocity of sound with modulus of elasticity and density of the medium. 2. Prove the following equations of motion graphically (i) S = ut + ½ at2 (ii) V2 = u2 + 2as. 3. What are the conditions of projectile motion? Show that path of projectile that is thrown from the ground is parabolic. 4. Define elasticity. Find an expression for energy stored in a stretched wire. 5. Derive the dimensional relation of stokes force with coefficient of viscosity, radius of spherical ball and terminal velocity of the ball in the viscous liquid. 6. You are given a brass rod in physics lab to find its linear expansivity. Describe the experiment to find it. 7. Define linear, superficial and cubical expansivities. Establish relation between them. 8. What is anomalous expansion of water? Derive the expression to find the relation of density of a liquid when the temperature is raised from 0oC to θoC. 9. How do you charge a conductor positively by the method of induction? 10. Define electric potential. Derive its expression.
Numerical problems 1. A spelunker is surveying a cave. She follows a passage 180 m straight west, then 210 m in a direction 45o east of south, and 280 m at 30o east of north. After the fourth unmeasured displacement, find her back where she started. Find the magnitude and direction of fourth displacement. 2. A car is stopped at a traffic light. It then travels along a straight road so that its distance from the light is given by X(t) = bt2 – ct3, where b= 2.40 m/s2 and c = 0.120 m/s 3 .Calculate the instantaneous velocity of the car at (i) t = 0 (ii) t= 5.0 s (iii) t = 10.0 s. 3. A bottle is filled with 250 cc of benzene at 30oC. If the bottle is cooled to 0oC, how much air space will there be above the bottle? Neglect the expansion of the bottle. [ Cubical expansivity for benzene is 12.4 x 10-4oC-1] 4. Two spheres of radii 5 cm and 10 cm are charged to potentials 300 V and 100 V respectively. What is the charge on each sphere? If the spheres are connected by a fine wire, what is the charge on each sphere? 5. A clock which has brass pendulum beats seconds correctly when the temperature of the room is 30oC. How many seconds will it gain or loss per day when the temperature of the room falls to 10oC. Given α of brass is 1.9 x 10-5/oC. 6. A convex mirror forms an image of half the size of the object. When it is moved 15 cm away from the object, the size of the image becomes 2/5 times the size of object. Find the focal length of convex mirror. 7. Two charges 20µC and 25µC are placed 2m apart in a dielectric medium of relative permittivity 20. Calculate total force between them.
Zoology
Short Questions a) Describe Miller Urey experiment. b) Draw a well labeled diagram of buccal cavity of a frog. c) Differentiate between Gnathostomata and Agnatha. d) Describe asexual mode of reproduction in Paramecium caudatum. e) Write primary volant characters of a bird. f) Describe the causes and effects of water pollution. g) Describe Pasteur’s experiment in favour of biogenesis. h) Differentiate between chondrichthys and ostiechthys. i) Describe the structure of sporozoite stage of Plamodium. j) List out the amphibian adaptation of a frog.
Long Questions 1. Describe the biochemical theory of origin of life. 2. With well labeled figure describe the structure of Paramecium caudatum. 3. Describe the physiology of digestion in frog. 4. Describe the conjugation process in Paramecium caudatum. 5. Describe alimentary canal of frog with well labeled diagram.
Botany
Short Questions a) Differentiate between prokaryotic and eukaryotic cell. b) Write significance of mitosis. c) Explain the structure of a bacterial cell. d) Give the advantages of five kingdom classification. e) Write the differences between Rhodophyceae and phaeophyceae. f) Describe the vegetative structure of Spirogyra. g) Write short note on 'Symbiosis’. h) Mention the drawbacks of two kingdom classification. i) Write the roles of bacteria in nitrogen fixation. j) How does scalariform conjugation occur in Spirogyra?
Long Questions 1. With well labeled diagram, describe ‘Pond Ecosystem’. 2. Describe the process of conjugation in Spirogyra. 3. Give the structure and economic importance of Nostoc. 4. What is mitosis? Explain the process of mitosis with necessary diagram. 5. Highlight the importance of Fungi.
Computer
From Unit 1
1. Explain any five application fields of computer in our society.
2. Compare and show distinction between 3rd and 4th generation of computers with example.
3. What is computer? Write the contribution of John Napier, Lady Ada and Dr. Herman Hollerith in the history of computer.
4. Why is Charles Babbage known as “the father of the today’s computer”?
5. Writes short notes on: a) EDVAC b) MICR c) Abacus
6. Computer play a vital role in the day-to-day life of human beings. Justify your answer.
7. Discuss the positive and negative impact of today’s digital computer on your society.
From Unit 2 1. Classify the computers on the basis of working principle and explain them. 2. Contrast and compare between supercomputer and micro computer with examples. 3. What are the main distinct features of 5th generation that makes it different from the other generations of computers?
4. What is analog computer? Elaborate the eight characteristics of analog computer with example.
5. What is digital computer? Elaborate the eight characteristics of analog computer with example.
From Unit 3
1. What is denary number system? Convert (6789)10 = ( ? ) 16 & (100111001)2 = ( ? ) 10 .
2. Perform the following binary operations: a) 1011+1101+1111=? b) 10010 - 1111=? c) 1011 X 1011=? d) 1110 ÷101=? e) 100111÷11=?
3. What is Hexadecimal number system? Convert (1234)10 into Binary number system.
4. Convert the following number systems according to the instruction: a) (BCD)16=(?)10 b) (101011001)2=(?)10 c) (1430)10=(?)8 d) (7651)8=(?)10 e) (0.101011)2=(?)10 f) (1010)10=(?)16
5. What is binary number system? Convert (1011101)2 into decimal number system.
6. Convert the following number systems according to the instruction: a) (1001)10=(?)16 b) (111100011)2=(?)10 c) (1.001101)2=(?)10 d) (7531)8=(?)10 e) (2561)10=(?)8 f) (CAB)16=(?)10
7. What is octal number system? Convert (FEE)16 into decimal number system. 2+3]
8. Convert the following number systems according to the instruction: a) (10.11001)2=(?)10 b) (1020)10=(?)16 c) (10101)8=(?)10 d) (999)10=(?)8 e) (BAD)16=(?)10 f) (10001100)2=(?)10
9. What is complement? Find the value of binary subtraction of (1001011 – 11011)2 using 1’s complement method.
From Unit 4
1. Construct the truth table for 3input NOR-gate and its logical operations with its symbol.
2. Construct truth table for 4 input NAND gate and draw its logical operations with symbol.
3. Writes short notes on: De Morgan’s law 4. What is logical gate? Construct the truth table of ‘AND’ and ‘OR’ operations with algebraic expressions. Differentiate between analog and digital computer with appropriate example. 5. What is Truth table? Draw Venn diagram of : a) X + Y b) X . Y + X . Y From Unit 5
1. Writes short notes on: a) ASCII b) MICR c) cache memory
2. What is bus architecture? Explain the different types of bus.
3. What are hardware, software and firmware? Give the suitable examples. 4. What do you mean by computer architecture? Describe each functional components/block of computer architecture with typical block diagram. 5. What is a memory? Draw its hierarchical diagram of memory. Distinguish between the primary and secondary memory in a computer system? [Give at least 8 points each.] 6. What is BUS architecture? Explain different types of bus architecture. 7. What is computer system? Draw a logical diagram of the computer system showing all elements and their interconnections. Explain these components in briefly. 8. Explain the hardcopy and softcopy output of the computer system with appropriate examples. 9. What are the main functions of CU and ALU in a computer system? Explain briefly. 10. What is computer architecture? Explain hardware, software and firmware with example. 11. . What is memory? Differentiate between RAM and ROM with eight points. 12. Explain the main function of control unit of computer system in details. 13. What is secondary memory? Distinguish between hard disk and optical disk. [Point out at least 8 points.] 14. What is input unit? Explain main function of arithmetic and logical unit (ALU) in detail. 15. What is Primary memory? Differentiate between SRAM and DRAM with six points. 16. What is bus architecture? Explain different types of bus architecture in detail. 17. What is non volatility? Distinguish between magnetic tape and floppy disk. [Point out at least 8 points.] 18. What is output unit? Explain function of central processing unit (CPU) in detail. 19. Explain the block diagram of computer with appropriate diagram. 20. What is ROM? Explain the ROM and its types in detail. 21. What is volatility? Differentiate between hard disk and floppy disk. [Point out at least 8 points.] 22. What is volatile memory? Illustrate an example. Differentiate between magnetic tape and optical disk in a computer system? [Give at least 8 points each.]
Practical unit
1. Distinguish between the MS-Windows and MS-Word? Point out the any six main features of them.
2. What is MS-DOS? What are the facial appearances of MS-DOS?
(Students are supposed to submit the vacation home assignment on the very first day after the Dashain-Tihar vacation.)