PRACTICE QUESTION PAPER WITH SOLUTION CLASS XI PHYSICS

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1 PRACTICE QUESTION PAPER WITH SOLUTION CLASS XI PHYSICS. A given quantity has both magnitude and direction. Is it necessarily a vector? Justify your answer.. What is the rotational analogue of the force?. State the two factors on which the modulus of elasticity depends. 4. The average velocity of a particle is equal to its instantaneous velocity. Draw the position-time graph of its motion.. Fast moving neutrons can be quickly slowed down by passing through water or heavy water. Why? 6. What do you mean by equilibrium of concurrent forces? What is the condition of equilibrium of a body under the action of three concurrent forces F, F, F? 7. An elevator of total mass 800 kg is moving up with a constant speed of ms -. The frictional force opposing the motion is 4000 N. Determine the minimum power delivered by the motor to the elevator. Take g = 0 ms - 8. Find the relation between torque and angular momentum. What is the physical significance of moment of inertia? What are the factors on which moment of inertia of a body depends? 9. A body rolled on ice with a velocity of 8 ms - comes to rest after travelling 4m. Compute the coefficient of friction. Given g = 0 ms - 0. Show that the average kinetic energy of a gas molecule is directly proportional to the temperature of the gas.. If a man goes from the surface of the earth to a height equal to the radius of the earth, then what will be his weight relative to that on earth? What if he goes equally below the surface of the earth?. A transverse harmonic wave on a string is described by y(x, t) =.0 sin(6t x + /4) where x and y are in cm and t in s. The positive direction of x is from left to right. (a) Is this a travelling wave or stationary wave? (b) What are its amplitude and frequency? (c) What is the initial phase at the origin? State Newton s laws of motion. ( laws) 4 (a) The error in the measurement of radius of a sphere is %. What would be the error in measurement of the volume of the sphere? (b) Find the dimensions of a and b in the equation : F = where F is force, x is distance and t is time. a x bt,

2 . State and prove Kepler s second law of planetary motion. 6. (a) Write the properties of conservative forces. (b) Prove that work done by the spring force in a cyclic process is zero. 7. Define terminal velocity. Derive an expression for the terminal velocity of a small spherical body falling through a viscous medium. Define the term angle of contact. Derive an expression for the rise of liquid in a capillary tube. 8. What are the assumptions of kinetic theory of gases? (6 main points) 9. A balloon is ascending at the rate of 9.8 ms -, at a height of 9. m above the ground when a food packet is dropped from the balloon. After how much time and with what velocity does it reach the ground? g = 9.8 ms - 0. State the law of conservation of linear momentum and derive it from Newton s second law of motion. Discuss one practical application of the law of conservation of momentum. State the theorem of parallel axes. Applying this theorem calculate the moment of inertia of a rod of mass M, length l about an axis perpendicular to it through one end.

3 . What is Doppler effect? Derive an expression for the apparent frequency of sound as heard by a stationary observer in a still medium, when the source is moving towards the observer with a uniform velocity.. State Pascal s law of transmission of fluid pressure. Explain how is Pascal s law applied in a hydraulic lift. 4 A copper block of mass. kg is heated in a furnace to a temperature of 00 0 C and then placed on large ice block. What is the maximum amount of ice that can melt? (Specific heat of copper = 0.9 J g - K - ; heat of fusion of water = J g - ) What do you mean by simple harmonic motion? Derive the expressions for kinetic energy, potential energy and total energy of a simple harmonic oscillator. Plot the variations of kinetic energy, potential energy and total energy as functions of position x of a particle executing simple harmonic motion. (a) Draw displacement time, velocity time and acceleration time graphs for a particle executing simple harmonic motion. (b) Show that for small oscillations the motion of a simple pendulum is simple harmonic. Derive an expression for its time period. 6. Describe the working of a refrigerator as a heat pump. Derive an expression for its coefficient of performance. Write the Clausius statement of second law of thermodynamics. What is a heat engine? Explain its working. Find an expression for the efficiency of a heat engine. 7. (a) State parallelogram law of vector addition. Two vectors A & B are inclined to each other at an angle. Using parallelogram law of vector addition, find the magnitude and direction of their resultant. (b) Prove that the maximum horizontal range is four times the maximum height attained by the projectile, when fired at an angle so as to have maximum horizontal range. (a) What do you mean by rectangular components of a vector? How can the position vector r of any point P (x,y) be expressed in terms of rectangular components? (b) A projectile is fired with a velocity u making an angle with the horizontal. Show that its trajectory is a parabola.

4 Position x Q. No. Value Points Marks Total. () No () For a quantity to be a vector it should obey the laws of vector addition.. Torque. () Nature of the material () Type of stress used in producing strain 4. time t. When neutrons undergo elastic collision with water, they exchange their velocities with hydrogen nuclei. Because hydrogen nuclei have roughly same mass as that of neutron.

5 6. () Definition () Vector diagram F + F + F = 0 7. F = mg + f = F = 000 N P = F.v = 000 = W 8. L r p dl d r p dt dt d r p dr dp p r dt dt dt dl dp r r F dt dt dl dt. Physical significance of moment of inertia. Any two factors on which M.I. of a body depends = a 4 a = 8 ms - ma a f / N mg g P v M = v. V PV M v, PV = RT from ideal gas equation ( mol) RT M v RT M v RT M N N mv kb K.E = K.E T k B T v T mgm. W h = mg h = ( R h) W h /W = mgm / 4R mgm / R = = 4 mgm ( R)

6 . W d = mg d = m(-r/r) = 0. a. travelling b. amplitude =.0 cm frequency =.7 Hz c. initial phase = /4. Each Law - mark 4. 4 a. V = r V r, X00 X00 V r = % = 6% b. (i) [a] = [ F] [ x] ] [ MLT = = [ML T - ] L (ii) [b] = [ F] [ t ] = ] [ MLT = [MLT -4 ] T. Statement of Kepler s II Law Diagram, A = ( r v t) A ( r x p )/m t = L /m 0, L Constant A Constant t 6. a. Properties mark each b. F s = -kx W s = W s = 0 xi xi kxdx 7. Definition of terminal velocity W = 4/ r g F = 6 r v U = 4/ r g Explanation of F + U = W r ( ) g Substitution & finding expression vt 9. Definition of angle of contact. Derivation of capillary rise by any one method +

7 Energy 8. Each point mark x 6 9. u = 9.8ms -, g = -9.8ms -, S = -9.m -9. = 9.8 t 9.8t Solution t = 4s v = u + gt = = -8.4 ms - 0. i) Statement of law of conservation of linear ii) momentum dp F dp, When F = 0, 0 dt dt P Constant iii) Discussion of one practical application. i) Statement of theorem of parallel axes ii) M.I. of the rod about an axis passing through the centre & r to it = Ml / M.I. of the rod about an axis r to it through one end, Ml I l M Ml I. i) Doppler Effect ii) Derivation of apparent frequency. Statement of Pascal s law Schematic diagram Explanation of working 4 Heat lost by copper block mc T = J Heat gained by ice = ML = M J Heat gained = Heat Lost Substitution & Calculation M =.4 kg. i) Definition of SHM ii) Expression for P.E iii) Expression for K.E iv) Expression for T.E v) Graph T.E. = K.E. + P.E P.E - A O +A K.E X

8 i. Displacement time graph ii. Velocity time graph iii. acceleration time graph iv. Diagram showing direction of forces v. Proof for S.H.M vi. T = l g 6. i. Diagram ii. Working of refrigerator iii. Coefficient of performance Q T Q Q T T iv. Clausius statement of II law of thermodynamics i. Definition heat engine ii. Diagram iii. Working iv. W Efficiency Q Q Q Q T Q Q T 7 i. Statement of parallelogram law of vector addition ii. Diagram iii. Calculation R = A B AB cos iv. Direction of the resultant v. Maximum horizontal range = u sin H max = g When = 4 o H max = u 4g u g H max = R max 4 a. i. Definition of rectangular components ii. Position vector r xiˆ yˆj iii. Diagram b. x = u cos t, Diagram y = u sin t g t substitution & equation for the trajectory of projectile +

9 KENDRIYA VIDYALAYA SANGATHAN (AHMEDABAD REGION) SESSION ENDING EXAMINATION CLASS XI PHYSICS (THEY) Time Allowed : Hours Maximum Marks : 70 DESIGN OF QUESTION PAPER. Weightage of Learning Outcomes Sl. No. Objective Marks Percentage. Knowledge 0. Understanding 0. Application 4 0 TOTAL Weightage to content / units Unit Marks. Physical World & Measurement 0. Kinematics 0. Laws of Motion 0 4. Work, Energy & Power 06. Motion of system of particles & Rigid Body Gravitation 0 7. Properties of Bulk Matter 0 8. Thermodynamics 0 9. Behaviour of Perfect Gas & Kinetic Theory of gases 0 0. Oscillations & Waves 0 TOTAL 70. Weightage to form of questions Sl. Form of Questions Marks for each No. of Total Marks No. Question Questions. Long Answer Type (LA). Short Answer Type (SAI) 6. Short Answer (SA II) Very Short Answer (VSA) TOTAL Weightage to difficulty level of questions Sl. Estimated Difficulty Level Percentage No.. Easy %. Average 0 %. Difficult %

10 KENDRIYA VIDYALAYA SANGATHAN (AHMEDABAD REGION) SESSION ENDING EXAMINATION CLASS XI PHYSICS (THEY) Time Allowed : Hours Maximum Marks : 70 BLUE PRINT OBJECTIVES Knowledge Understanding Application Units VSA SAII SAI LA VSA SAII SAI LA VSA SAII SAI LA. Physical World & Measurement () (). Kinematics () () () () 0 (4). Laws of Motion () () () () 0 (4) 4. Work, Energy & Power () () () 6 (). Motion of system of particles & Rigid Body () () () 6 () 6. Gravitation () () () 7. Properties of Bulk Matter () () () 0 (4) 8. Thermodynamics () () 9. Behaviour of Perfect Gas & Kinetic Theory of gases () () () 0. Oscillations & Waves () () () 0 () TOTAL (9) () 4 (6) 70 (7) Total