KVS Gurgaon Summer Vacation 2017-18 Holiday Home Work (Business studies) Project: Application and principle of Mgt. in PIZZA HUT, BURGER KING, KFC, BIG BAZZAR etc. Chapter: 1 Self-evaluation Test Page no. 35 to 36 Chapter: 2 Self- Evaluation Test Page no. 63 to 64 Chapter 3: Business Environment Self Evaluation Test Page 81 to 82. (Accountancy) Scanner: Page S.20 to S.32 fundamental Page S.33 to S.35 Goodwill Page 36 to 39 Change in profit sharing ratio. Page 39 to 45 till Q. 17 Admission of a partner. Project: PAGE p.26,27,28,29,30,31,32,33,34,35,36,38 Comprehensive: 1 Prepare trial balance, Trading A/C, Profit and Loss A/C and Balance Sheet + Accounting Ratio (Page 40 and 41) Bar diagram and Cash Flow Statement
Transcript
KVS Gurgaon
Summer Vacation 2017-18
Holiday Home Work
(Business studies)
Project: Application and principle of Mgt. in PIZZA HUT, BURGER KING, KFC, BIG BAZZAR etc.
Chapter: 1 Self-evaluation Test Page no. 35 to 36
Chapter: 2 Self- Evaluation Test Page no. 63 to 64
Chapter 3: Business Environment Self Evaluation Test Page 81 to 82.
(Accountancy)Scanner: Page S.20 to S.32 fundamental
Prepare trial balance, Trading A/C, Profit and Loss A/C and Balance Sheet + Accounting Ratio
(Page 40 and 41)
Bar diagram and Cash Flow Statement
Economics
Do 5 Practical on PPF. Do any 2 practical on TU and MU. Do any 2 practical on Opportunity Cost Do any 2 practical on consumer’s equilibrium (single commodity) Do any 2 practical on consumer’s equilibrium ( two commodity) Learn chapter no. 1,2and 3. Write notes on following topics:
a. Consumer’s equilibrium in case of single commodity. b. Consumer’s equilibrium in case of two commodity.c. Consumer’s equilibrium in indifference curve analysis.d. Law of DMU.
IT CLASS AND OBJECT
[SET – 1]
Question 1 Define a class student with the following specificationPrivate members of class studentadmno integersname 20 charactereng. math, science floattotal floatctotal() a function to calculate eng + math + science with float return type.Public member function of class studentTakedata() Function to accept values for admno, sname, eng, science
and invoke ctotal() to calculate total.Showdata() Function to display all the data members on the screen.
Question 2 Define a class batsman with the following specifications:Private members:bcode 4 digits code numberbname 20 charactersinnings, notout, runs integer typebatavg it is calculated according to the formula batavg =runs/(innings-notout)calcavg() Function to compute batavgPublic members:readdata() Function to accept value from bcode, name, innings, notout and invoke the function calcavg()displaydata() Function to display the data members on the screen.
Question 3 Define a class TEST in C++ with following description:Private MembersTestCode of type integerDescription of type stringNoCandidate of type integerCenterReqd (number of centers required) of type integerA member function CALCNTR() to calculate and return the number of centers as(NoCandidates/100+1)Public Members - A function SCHEDULE() to allow user to enter values for TestCode, Description, NoCandidate & call function CALCNTR() to calculate the number of Centres- A function DISPTEST() to allow user to view the content of all the data members
Question 4 Define a class in C++ with following description:Private MembersA data member Flight number of type integerA data member Destination of type stringA data member Distance of type floatA data member Fuel of type floatA member function CALFUEL() to calculate the value of Fuel as per the following criteriaDistance Fuel<=1000 500more than 1000 and <=2000 1100more than 2000 2200Public MembersA function FEEDINFO() to allow user to enter values for Flight Number, Destination, Distance & call function CALFUEL() to calculate the quantity of FuelA function SHOWINFO() to allow user to view the content of all the data members
Question 5 Define a class BOOK with the following specifications :Private members of the class BOOK areBOOK NO integer typeBOOKTITLE 20 charactersPRICE float (price per copy)TOTAL_COST() A function to calculate the total cost for N number of copies where N is passed to the function as argument. Public members of the class BOOK areINPUT() function to read BOOK_NO. BOOKTITLE, PRICEPURCHASE() function to ask the user to input the number of copies to be purchased. It invokes TOTAL_COST() and prints the total
cost to be paid by the user. Note : You are also required to give detailed function definitions.
Question 6 Define a class REPORT with the following specification:Private members :adno 4 digit admission numbername 20 charactersmarks an array of 5 floating point valuesaverage average marks obtainedGETAVG() a function to compute the average obtained in five subjectPublic members:READINFO() function to accept values for adno, name, marks. Invoke
the function GETAVG() DISPLAYINFO() function to display all data members of report on the screen.You should give function definitions.
EnglishClass XII A & B-
(To learn and write In a separate notebook for Summer Vacation HW)
-4 classified & 2 Non Classified Advertisement
-2 Formal invitations+ 2 Informal Invitations
- Reply to Invitations (2 Formal+ 2 Informal)
-2 Notice
-2 Letters to Editor
-2 Business letters
-1 articles
-1 speech,1 debate
-2 Note Making
2.Read the original text of The Invisible Man (All chapters) & Write Chapter wise Summary in Separate Notebook
3.Learn
-Summary/Gist & Question-Answers of all the chapters already completed.
PHYSICS
Year wise questions from CBSE board examination
UNIT –I ELECTROSTATICS (8marks)
CBSE 2014:
1. "For any charge configuration, equipotential surface through a point is normal to the electric field." Justify.
[1
2. Given a uniform electric field N/C, find the flux of this field through a square of 10 cm on a side whose plane is parallel to the y-z plane. What would be the flux through the same square if the plane makes a 30° angle with the x-axis? [2
3. An electric dipole of length 4 cm, when placed with its axis making an angle of 60° with a
uniform electric field, experiences a torque of Nm. Calculate the potential energy of the dipole, if it has charge ±8 nC.
[2
4. (a) Obtain the expression for the energy stored per unit volume in a charged parallel plate capacitor.
[3
(b) The electric field inside a parallel plate capacitor is E. Find the amount of work done in moving a charge q over a closed rectangular loop abcda
OR
(a) Derive the expression for the capacitance of a parallel plate capacitor having plate area A and plate separation d.
(b) Two charged spherical conductors of radii R1 and R2 when connected by a conducting wire acquire charges q1, and q2 respectively. Find the ratio of their surface charge densities in terms of their radii.
5. (Set II) An electric dipole of length 2 cm, when placed with its axis making an angle of 60° with a
uniform electric field, experiences a torque of Nm. Calculate the potential energy of the dipole, if it has a charge of ± 4 nC.
[2
6. (Set II) Given a uniform electric field N/C, find the flux of this field through a square of side 20 cm, whose plane is parallel to the y-z plane. What would be the flux through the same square, if the plane makes an angle of 30° with the x-axis?
[2
7. (Set III) An electric dipole of length 1 cm, which placed with its axis making an angle of 60° with
uniform electric field, experiences a torque of Nm. Calculate the potential energy of the dipole if it has charge ± 2 nC.
[2
CBSE 2013:
8. What is the geometrical shape of equipotential surface due to a single isolated charge? [1
9. A capacitor of unknown capacitance is connected across a battery of V volts. The charge stored in it is 360 µC. When potential across the capacitor is reduced by 120 V, the charge stored in it becomes 120 µC. Calculate : [3(i) The potential V and the unknown capacitance C. (ii) What will be the charge stored in the capacitor, if the voltage applied had increased by
120 V? OR
A hollow cylindrical box of length 1 m and area of cross-section 25 cm 2 is placed in a three dimensional coordinate system as shown in the figure. The electric field in the region is given by E=50 x i , where E is in NC – 1 and x is in metres. Find
(i) Net flux through the cylinder. (ii) Charge enclosed by the cylinder.
10. While travelling back to his residence in the car, Dr. Pathak was caught up in a thunderstorm. It became very dark. He stopped driving the car and waited for thunderstorm to stop. Suddenly he noticed a child walking alone on the road. He asked the boy to come inside the car till the thunderstorm stopped. Dr. Pathak dropped the boy at his residence. The boy insisted that Dr. Pathak should meet his parents. The parents expressed their gratitude to Dr. Pathak for his concern for safety of the child. Answer the following questions based on the above information: (a) Why is it safer to sit inside a car during a thunderstorm? [4(b) Which two values are displayed by Dr. Pathak in his actions? (c) Which values are reflected in parents' response to Dr. Pathak? (d) Give an example of a similar action on your part in the past from everyday life.
11. (Set III) A capacitor of unknown capacitance is connected across a battery of V volts. The charge stored in it is 300 µC. When potential across the capacitor is reduced by 100 V, the charge stored in it becomes 100 µC. Calculate :
(iii) The potential V and the unknown capacitance C. (iv) What will be the charge stored in the capacitor, if the voltage applied had increased by
100 V?
OR
A hollow cylindrical box of length 0.5 m and area of cross-section 20 cm2 is placed in a three dimensional coordinate system as shown in the figure. The electric field in the region is given by E=20 x i , where E is in NC – 1 and x is in metres. Find
(iii) Net flux through the cylinder. (iv) Charge enclosed by the cylinder.
CBSE 2012:
12. A charge 'q' is placed at the centre of a cube of side l. What is the electric flux passing through each face of the cube? [1
13. 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, [2(i) Calculate the potential difference between A and C. (ii) At which point (of the two) is the electric potential more and why?
14. An electric dipole is held in a uniform electric field. [2(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 through the
angle of 180°. 15. Deduce the expression for the electrostatic energy stored in a capacitor of capacitance 'C' and
having charge 'Q’. [3
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’?
16. (SET-2) A charge ‘q’ is placed at the centre of a cube of side l. What is the electric flux passing through two opposite faces of the cube?
[1
17. (SET 2) 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, [2(i) Calculate the potential difference between A and C. (ii) At which point (of the two) is the electric potential more and why?
18. (SET -3) A charge 'q' is placed at the centre of a cube. What is the electric flux passing through the cube?
[1
19. (SET-3) 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?
CBSE 2011:
1. Define electric dipole moment. Write its S.I. unit. [1
2. A hollow metal sphere of radius 5 cm is charged such that the potential on its surface is 10 V. What is the potential at the centre of the sphere?
[1
3. A thin straight infinitely long conducting wire having charge density X is enclosed by a cylindrical surface of radius r and length I, its axis coinciding with the length of the wire. Find the expression for the electric flux through the surface of the cylinder.
[2
4. Plot a graph showing the variation of Coulomb force (F) versus where r is the distance between the two charges of each pair of charges: (1 μC, 2 μC) and (2 μC, - 3 μC). Interpret the graphs obtained.
[2
5. Net capacitance of three identical capacitors in series is 1 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.
[2 6. 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? [1
7. 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.
[2
8. Plot a graph showing the variation of Coulomb force (F) versus where r is the distance between the two charges of each pair of charges: (1 μC, 2 μC) and (2 μC, – 3 μC). Interpret the graphs obtained.
[2 9. A hollow metal sphere of radius 6 cm is charged such that the potential on its surface is 12
V. What is the potential at the centre of the sphere? [1
10. Net capacitance of three identical capacitors in series is 3 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.
[2
CBSE 2010:
20. Name the physical quantity whose S.I. unit is J C – 1. Is it a scalar or a vector quantity? [1
21. 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.
[2(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.
22. Show that the electric field at the surface of a charged conductor is given by , where σ is the surface charge density and is a unit vector normal to the surface in outward direction. [2
23. A network of four capacitors each of 12 μF capacitance is connected to a 500 V supply as shown in the figure. Determine (a) equivalent capacitance of the network and (b) charge on each capacitor. [3
CBSE 2009:
1. What is electrostatic potential due to electric dipole at an equatorial point? [1 2. Draw 3 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? [2
3. Define Electric flux. Writ 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? [2
4. A +q point charge is kept in the vicinity of an uncharged conducting plate. Sketch electric field lines originating from the point on the surface of the plate. Derive the expression for the electric field at the surface of a charged conductor.
[3 OR
A parallel plate capacitor is charged by a battery. After some time battery is disconnected and dielectric slab (K) is inserted between the plates. How would (i) capacitance (ii) electric field (iii) energy stored be affected? Justify your answer.
CBSE 2008:
1. Which orientation of an electric dipole in a uniform electric field would correspond to stable equilibrium?
[1 2. (Set-II) If the radius of Gaussian surface enclosing a charge is halved, how does the electric flux
through the Gaussian surface change? [13. (Set-III)Define the term electric dipole moment of a dipole. State its S.I. unit. [1 4. Two point charges 10 × 10 – 8C and – 2 × 10 – 8C are separated by a distance of 60cm in air. (i)Find
at what distance from first charge, the electric potential is zero. (ii) Also calculate the electrostatic potential energy of the system.
[2OR
Two point charges 4Q and Q are separated by 1m in air. At what point on the line joining the two charges is the electric field intensity is zero? Also calculate the electrostatic potential energy of the system of charges, taking the value of charge, Q= 2 × 10 – 7C.
5. Derive an expression for the energy stored in a parallel plate capacitor. On charging a parallel plate capacitor to potential V, the spacing between the plates is halved, and a dielectric medium of K=10 is introduced between the plates, without disconnecting the d.c source. Explain using suitable expressions, how the (i) capacitance,(ii)electric field and (ii) energy density of the capacitor change.
[5OR
(a) Define electric flux. Write its S.I. units.
(b) The electric field components due to a charge inside the cube of side 0.1m are as shown:
Ex= ax , where a=500N/C-m Ey =0 , Ez= 0
Calculate (i) the flux through the cube, and (ii) the charge inside the cube.
CBSE 2007:
1. Two point charges 4µC and -2µC are separated by a distance of 1m in air. Calculate at what point on the line joining the two charges is the electric potential zero.
[2
2. State Gauss’s theorem. Apply this theorem to derive an expression for the electric field intensity at a point near an infinitely long, thin uniformly charged straight wire. / (set II uniformly charged spherical shell.)
[3 3. Explain the underlying principle of working of a parallel plate capacitor. If two similar plates,
each of area A having surface charge densities +σ and -σ are separated by a distance d in air, write expressions for i) electric field at points between the plates. ii) potential difference between the plates iii) capacitance of capacitor so formed.
[3
CBSE 2006:
1. Define electric dipole moment. Is it a scalar or a vector quantity? [1
2. A point charge ‘q’ is placed at O as shown in the figure. Is VP – VQ positive or negative when (i) q >0 ,(ii) q< 0? O _______P____Q Justify your answer. [2
3. Two capacitors of capacitance 6µF and 12µF are connected in series with a battery. The voltage across the 6µF is 2 V Compute the total battery voltage.
[2 OR
A parallel plate capacitor with air between the plates has a capacitance of 8µF.The separation `between the plates is now reduced by half and the space is filled with K=5. Calculate the value of capacitance in the second case.
4. Using Gauss’s theorem, show mathematically that for any point outside the shell, the field due to a uniformly charged thin shell is the same as if the entire charge of the shell is concentrated at the centre. Why do you expect the electric field inside the shell to be zero according to this theorem?3
CBSE 2005:
1. (set I)An electrostatic field line cannot be discontinuous. Why? [12. (set II) How does the coulomb force between two charges depend on intervening medium?[13. (set III) Two electric lines never intersect each other. Why?
[14. Define Electric field intensity. Write its SI unit. Write the magnitude and direction of E due to dipole of
length 2a at the midpoint of line joining two charges. [2 5. (set I) A parallel plate capacitor is to be designed with voltage rating 1kV using a material of
K=3 and dielectric strength 107 V/m. For safety we would like the field never to exceed say, 10% of the dipole strength. What minimum area of the plates is required to have a capacitance of 50 pF? [2
6. (set II) A charge q is placed at the centre of line joining two equal charges Q. Show that the system of three charges will be in equilibrium if q = -Q/4.
[2
7. (set III) Two fixed charges +4e and +e are separated by a distance ‘a’. Where should the third point charge be placed for it to be in equilibrium?
[2OR
A 4µF capacitor is charged by a 200V supply. The supply is then disconnected and the charged capacitor is connected to another uncharged 2µF capacitor. How much electrostatic energy of the first capacitor is lost in the process of attaining the steady situation?
8. State Gauss’ theorem. Apply this theorem to obtain the expression for the electric field intensity at a point due to infinitely long, thin, uniformly charged straight wire. [3
CBSE 2004:
1. An electric dipole of length 4cm, when placed with its axis making an angle of 60o with uniform electric field experiences a torque of 4 /3Nm. Calculate the (i) magnitude of electric field, (ii)the potential energy of dipole ,if the dipole has charges of +8nC. [2
2. A 10µF capacitor is charged by a 30V d.c. and then connected across an uncharged 50µF capacitor. Calculate (i) the final potential difference of the combination, and (ii) the initial and final energies. How will you account for the difference in energy? [3
3. (set I, II) State Gauss’ theorem. Using this theorem to obtain the expression for the electric field intensity due to infinite plane sheet of charge of charge density σ C /m2. [3
4. (set I, II) State Gauss’ theorem. Use this theorem to obtain the expression for the E at any point outside a uniformly charged spherical shell. [3
UNIT –II CURRENT ELECTRICITY (7marks)
CBSE 2014 :(Delhi Sets)
1. Define the term 'Mobility' of charge carriers in a conductor. Write its S.I. unit. [1
2. Show variation of resistivity of copper as a function of temperature in a graph. [1
3. State Kirchhoff s rules. Explain briefly how these rules are justified. [2
4. A potentiometer wire of length 1 m has a resistance of 10 Ω. It is connected to a 6 V battery in series with a resistance of 5 Ω. Determine the emf of the primary cell which gives a balance point at 40 cm.
[3
5. (Set II) Define the term 'electrical conductivity' of a metallic wire. Write its S.I. unit. [1
6. (Set II) Show variation of resistivity of Si with temperature in a graph. [1
7. (Set II) A potentiometer wire of length 1.0 m has a resistance of 15 Ω. It is connected to a 5 V battery in series with a resistance of 5 Ω. Determine the emf of the primary cell which gives a balance point at 60 cm. [3
8. Define the term 'drift velocity' of charge carriers in a conductor and write its relationship with the current flowing through it.
[1
9. Plot a graph showing variation of current versus voltage for the material GaAs. [1
10. A potentiometer wire of length 1 m has a resistance of 5 Ω. It is connected to a 8 V battery in series with a resistance of 15 Ω. Determine the emf of the primary ceil which gives a balance point at 60 cm. [3
CBSE 2013 :(Delhi Sets)
11. A 10 V battery of negligible internal resistance is connected across a 200 V battery, and a resistance of 38 Ω as shown in the figure. Find the value of the current in circuit.
[1
12. The emf of a cell is always greater than its terminal voltage. Why? Give reason. [1
13. (a) State the working principle of a potentiometer. With the help of the circuit diagram, explain how a potentiometer is used to compare the emf's of two primary cells. Obtain the required expression used for comparing the emfs.
[5(b) Write two possible causes for one sided deflection in a potentiometer experiment.
OR
(a) State Kirchhoff s rules for an electric network. Using Kirchhoff s rules, obtain the balance condition in terms of the resistances of four arms of Wheatstone bridge.
(b) In the meter bridge experimental set up, shown in the figure, the null point 'D' is obtained at a distance of 40 cm from end A of the meter bridge wire. If a resistance of 10 Ω is connected in series with R1 null point is obtained at AD = 60 cm. Calculate the values of R1 and R2.
14. (SET II) A cell of emf 'E' and internal resistance 'r' draws a current 'I'. Write the relation between terminal voltage 'V' in terms of E, I and r.
[1
15. (SET II) A heating element is marked 210 V, 630 W. What is the value of the current drawn by the element when connected to a 210 V dc source?
[1
16. (SET III) A 5 V battery of negligible internal resistance is connected across a 200 V battery and a resistance of 39 Ω. as shown in the figure. Find the value of the current. [1
17. A heating element is marked 210 V, 630 W. Find the resistance of the element when connected to a 210 V dc source.
[1
CBSE 2012 : (Delhi Sets)
1. When electrons drift in a metal from lower to higher potential, does it mean that all the free electrons of the metal are moving in the same direction?
[1
2. Show on a graph, the variation of resistivity with temperature for a typical semiconductor. [1
3. A cell of emf E and internal resistance r is connected to two external resistances R1 and R2 and a perfect ammeter. The current in the circuit is measured in four different situations: (i) without any external resistance in the circuit. (ii) with resistance R1 only (iii) with R1 and R2 in series combination (iv) with R1 and R2 in parallel combination. The currents measured in the four cases are 0.42 A,
1.05 A, 1.4 A and 4.2 A, but not necessarily in that order. Identify the currents corresponding to the four cases mentioned above.
[2
4. In the figure a long uniform potentiometer wire AB is having a constant potential gradient along its length. The null points for the two primary cells of emfs e1and e2 connected in the manner shown are obtained at a distance of 120 cm and 300 cm from the end A. Find ( i) e1 / e2 and (ii) position of null point for the cell e1. How is the sensitivity of a potentiometer increased?
[3
OR
Using Kirchoff’s rules determine the value of unknown resistance R in the circuit so that no current flows through 4 W resistance. Also find the potential difference between A and D.
CBSE 2011 : (Delhi Sets)
1. A resistance R is connected across a cell of emf e and internal resistance r. A potentiometer now measures the potential difference between the terminals of the cell as V. Write the expression for ‘r’ in terms of e, V and R.
[1 2. Define the terms (i) drift velocity, (ii) relaxation time. A conductor of length L is connected to a
dc source of emf e. If this conductor is replaced by another conductor of same material and same area of cross-section but of length 3L, how will the drift velocity change?
[3
3. In the circuit shown, R1 = 4 Ω, R2 = R3 = 15 Ω, R4 = 30 Ω and E = 10 V. Calculate the equivalent resistance of the circuit and the current in each resistor.
[3
4. SET II In the circuit shown, R1 = 4 Ω, R2 = R3 = 5 Ω, R4 = 10 Ω and E = 6 V. Work out the equivalent resistance of the circuit and the current in each resistor. [3
5. SET III In the circuit shown, R1 = 2 Ω, R2 = R3 =10 Ω, R4 = 20 Ω and E = 6 V. Work out the equivalent resistance of the circuit and the current in each resistor. [3
CBSE 2010 :
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 electron in X is twice that in Y, find the ratio of drift velocity in the two wires.
[12. 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 terminal of the cell are also connected to a resistance of 5 Ω as shown in the circuit, the voltmeter reading drops to 1.8 V. find the internal resistance of the cell.
[3
3. State Kirchhoff’s rules. Use these rules to write the expressions for the current I1, I2 and I3 in the circuit diagram shown. [3
4. (set II) 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 2.0 V. when the terminal of the cell are also connected to a resistance of 3 Ω as shown in the circuit, the voltmeter reading drops to 1.5 V. find the internal resistance of the cell.
[3
5. (set II) State Kirchhoff’s rules. Use these rules to write the expressions for the current I1, I2 and I3
in the network. [3
(set III) 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 2.5 V. when the terminal of the cell are also connected to a resistance of 5 Ω as shown in the circuit, the voltmeter reading drops to 2.0 V. find the internal resistance of the cell.
[3
6. (set III) State Kirchhoff’s rules. Apply these rules to the loops PRSP and PRQP to write the expressions for the current I1, I2 AND I3 in the given circuit. [3
CBSE 2009 :
1. Calculate the current drawn from the battery from the given network. [2
2. A wire of resistance 15 Ω is gradually stretched to double its original length. It is then cut into two equal parts. These parts are then connected in parallel across a 3 V battery. Find the current drawn from the battery.
[23. (a) State the principle of working of Meter Bridge.
[3(b) In the meter bridge balance point is found at a distance l1 with resistance R and S as shown in figure.
When an unknown resistance X is connected in parallel with the resistance S, the balance point shifts to a distance l2. Find the expression for X in terms of l1, l2 and S.
4. (set III) A wire of resistance 20 Ω is gradually stretched to double its original length. It is then cut into two equal parts. These parts are then connected in parallel across a 4 V battery. Find the current drawn from the battery.
[2CBSE 2008:
1. Two metallic wires of the same material have the same length but cross-sectional area is in the ratio 1:2. They are connected (i) in series (ii) parallel. Compare the drift velocities of electrons in the two wires in both the cases (i) and (ii).
[2 2. Derive an expression for the resistively of a good conductor, in terms of the relaxation time of
electrons. (set II) Using the mathematical expression for the conductivity of a material, explain how it varies with temperature for (i) semiconductors, (ii) good conductors. (Set III) Derive an expression for the current density of a conductor, in terms of drift speed of electrons.
[2 3. (i) Calculate the equivalent resistance of the given electrical network between points A and B.
(ii) Also calculate the current through CD and ACBG, if a 10V d.c. source is connected between A and B, and the value of R is assumed as 2Ω. [3
CBSE 2007:
1. A voltage of 30V is applied across a carbon resistor with first, second and third rings of blue, black and yellow colors respectively. Calculate the value of current, in mA, through the resistor.2
2. A cylindrical metallic wire is stretched to increase its length by 5 %. Calculate the percentage change in its resistance.
[2 3. For the potentiometer circuit shown in the given figure(a), points X and Y represent the two
terminals of an unknown emf E’. A student observed that when the jockey is moved from the end A to the end B of the potentiometer wire, the deflection in galvanometer remains in same direction. [3
What may be the two possible faults in the circuit that could result in this observation? If the galvanometer deflection at the end B is (i) more, (ii) less than that at the end A, which of the two faults , listed above, would be there in the circuit? Give reasons in support of your answer in each case.
OR
The given figure shows a network of resistances R1, R2, R3 and R4.
Using Kirchhoff’s laws, establish the balance condition for the network.
CBSE 2006:
1. The variation of p.d V with length l in case of two potentiometer A and B is as shown. Which one of these two will you prefer for comparing emfs of two primary cells? [1
2. Draw a circuit diagram using meter bridge and write the necessary mathematical relation used to determine the value of an unknown resistance. Why cannot such an arrangement be used for measuring very low resistances?
[2 3. You are given ‘n’ resistors, each of values ‘r’. These are first connected to get minimum possible
resistance. In the second case, these are again connected differently to get maximum possible resistance. Compute the ratio between the minimum and maximum values of resistance so obtained.
[2
CBSE 2005:
1. How does the resistivity of (i) conductor and (ii) semiconductor vary with temperature? Give reason for each case (set II) Establish a relation between current and drift velocity (set III) How do you convert galvanometer into ammeter? Why is ammeter always connected in series? [2
2. Two cells of e.m.f. 1.5V and internal resistance 1ohm and 2 ohm respectively are connected in parallel to pass a current in the same direction through an external resistance of 5 ohm.(a) Draw the circuit diagram. (b) Using Kirchhoff’s laws, calculate the current through each branch of the circuit and pd across 5 ohm resistor. (Set III) A series battery of 6 lead accumulators of emf2.0V and internal resistance 0.5ohm is charged by 100V d.c. supply. What series resistance should be used in the charging circuit in order to limit the current to 8A? Using the required resistor, obtain (i) power supplied by the d.c. source (ii) the power dissipated as heat.
[3
CBSE 2004:
1. Explain how does the resistivity of a conductor depend upon (i) number density ‘n’ of free electrons, and (ii) relaxation time. (SetII) Explain, with help of graph, the variation of conductivity with the temperature for a metallic conductor. [2
2. The circuit diagram shows the use of potentiometer to measure small e.m.f. produced by thermocouple connected between X and Y. The cell C, of e.m.f. 2V has negligible internal resistance. The potentiometer wire PQ is 1m long and has resistance 5Ω . The balance point S is found t0 be 400 mm from P. Calculate the value of e.m.f. V, generated by the thermocouple.
(Set III) Potentiometer wire, PQ of length 1m is connected to standard cell E1. Another cell, E2=1.02V is connected as shown With switch S open ,null point is obtained at 51cm from P. Calculate (i) Potential gradient of wire, (ii) e.m.f. of E1. (iii) When switch S is closed, will the null point move towards Q? Give reason for your answer. [3
WE
Explain different types of rectifiers with circuit diagram and waveforms.
XII A 1.Solve all the exercise &intext questions of unit 1 to 3.2.Solve one numerical per day(total 40) equally from 3 chapters.3.Write all formulae ofphy.Chem& learn.4.Biomolecules& chemistry in everyday life-Prapare notes & solve exercise questions.5.One investigatory project from the given topics.
Chemistry
Math
Properties of determinants(4 marks) USE Ri→ R i+ kR j or Ci→ C i + kC j Make three one’s then two zero
Using the properties of determinants, show that
1.
|1 x x2
1 y y2
1 z z2|
= (x – y)(y –z)(z – x) (C.B.S.E. 1991)
2.
|1 1 1α β γβγ γα αβ
| =(α−β )( β−γ )(γ −α ) C.B.S.E. 2006,
04)
3.
|1 a a3
1 b b3
1 c c3|
= (a - b)(b - c)(c - a)(a + b + c) (C.B.S.E. 1997, 96 ,2000, 2003C)
