This Question Paper contains of 30 questions and 8 Printed pages. ß Ÿ- òê apple 30 Ÿ ÃÕÊ 8 ÈÁŒ à Îc U Ò Roll No. ŸÈ Ê Day and Date of Examination ( UˡÊÊ Ê ÁŒŸ fl ÁŒŸÊ ) PHYSICS ÊÒÁà ÁflôÊÊŸ (3) Code No. Êapple«U Ÿ.5/OSS/ Set / apple UA Signature of Invigilators. (ÁŸ UËˇÊ Êapple apple SÃÊˇÊ U). General Instructions :. Candidate must write his/her Roll Number on the first page of the Question Paper.. Please check the Question Paper to verify that the total pages and total number of questions contained in the Question Paper are the same as those printed on the top of the first page. Also check to see that the questions are in sequential order. 3. Making any identification mark in the Answer-Book or writing Roll Number anywhere other than the specified places will lead to disqualification of the candidate.. Write your Question Paper Code No. 5/OSS/-A on the Answer-Book. 5. (a) The Question Paper is in English/Hindi medium only. However, if you wish, you can answer in any one of the languages listed below : English, Hindi, Urdu, Punjabi, Bengali, Tamil, Malayalam, Kannada, Telugu, Marathi, Oriya, Gujarati, Konkani, Manipuri, Assamese, Nepali, Kashmiri, Sanskrit and Sindhi. You are required to indicate the language you have chosen to answer in the box provided in the Answer-Book. (b) If you choose to write the answer in the language other than Hindi and English, the responsibility for any errors/mistakes in understanding the question will be yours only. Ê Êãÿ ŸÈŒapple Ê. UˡÊÊÕË Ÿ- òê apple apple Îc U U ŸÊ ŸÈ Ê fl ÿu Á πapple. Î ÿê Ÿ- òê Êapple ÊÚ ø apple Á Ÿ- òê apple È Îc UÊapple ÃÕÊ ŸÊapple Ë ÃŸË Ë ÅUÿÊ Ò Á ÃŸË Õ Îc apple apple U U Ë Ò ß ÊÃ Ë ÊÚ ø Ë U apple Á Ÿ Á UM apple Ò 3. ûê U- ÈÁSUÃ Ê apple øêÿ-áøq ŸÊŸapple ÕflÊ ÁŸÁŒ c U SÕÊŸÊapple apple ÁÃÁ UÄÃ Ë Ë ŸÈ Ê Á πÿapple U UˡÊÊÕË Êapple ÿêappleçÿ U UÊÿÊ ÊÿappleªÊ. ŸË ûê U- ÈÁSUÃ Ê U Ÿ- òê Ë Êapple«U ÅÿÊ 5/OSS/-A Á πapple 5. ( ) Ÿ- òê apple fl Á ŒË/ ª apple Ë apple Ò Á» U Ë, ÿáœ Ê øê apple ÃÊapple ŸËøapple ŒË ªß Á Ë Ê Ê apple ûê Œapple Ãapple Ò ª apple Ë, Á ŒË, ŒÍ, Ê Ë, ª Ê, ÃÁ, ÿê, ãÿ«, Ãapple ȪÍ, UÊ UË, Á«ÿÊ, ªÈ UÊÃË, Êapple áêë, ÁáÊ È UË, Á ÿê, Ÿapple Ê Ë, Ë UË, S Î Ã ÊÒ U Á œë Î ÿê ûê U- ÈÁSÃ Ê apple ÁŒ ª ÊÚÄ apple Á πapple Á Ê Á Ê Ê apple ûê U Á π U apple Ò (π) ÿáœ Ê Á ŒË fl ª apple Ë apple ÁÃÁ UÄà Á Ë ãÿ Ê Ê apple ûê U Á πãapple Ò ÃÊapple Ÿ Êapple ÊŸapple apple ÊappleŸapple flê Ë òêèá UÿÊapple /ª ÁÃÿÊapple Ë Á ê appleuœê Ë apple fl Ê Ë ÊappleªË!5/OSS/-3-A! [ Contd...
PHYSICS ÊÒÁà ÁflôÊÊŸ (3) Time : 3 Hours ] [ Maximum Marks : 80 ÿ 3 ÉÊá appleu ] [ ÍáÊÊZ 80 Note : (i) All questions are compulsory. (iii) Marks allotted are indicated against each question. Each question from Question No. to 0 has four alternatives - (A), (B), (C) and (D) out of which one is most appropriate. Choose the correct answer among the four alternatives and write it in your answer-book against the Number of the question. No separate time is allotted for attempting multiple-choice questions. ÁŸŒapple Ê (i) Ë Ÿ ÁŸflÊÿ Ò àÿapple Ÿ apple Ê Ÿapple Œ ÊÊ ÿapple ªÿapple Ò (iii) Ÿ Ê apple 0 apple àÿapple Ÿ apple øê U Áfl À - (A), (B), (C) ÊÒ U (D) ÁŒÿapple ªÿapple Ò, Á Ÿ apple Ë Ò øê UÊapple Áfl À Êapple apple apple Ë ûê U øèáÿÿapple ÃÕÊ ŸË ûê U- ÈÁSÃ Ê apple Ÿ Ê apple Ê Ÿapple Á Áπÿapple ÈflÒ ÁÀ ŸÊapple apple Á ÁÃÁ UÄà ÿ Ÿ Ë ÁŒÿÊ ÊÿappleªÊ. Which one of the following is not a characteristic of musical sound? (A) Wave velocity (B) Loudness (C) Pitch (D) Quality ÁŸêŸÁ Áπà apple ÊÒŸ- Ê ªËà ÿ äfláÿ Ê Á ˇÊáÊ Ÿ Ë Ò? (A) à Uªflappleª (B) ÃÊ (C) ÃÊ Uûfl (D) ªÈáÊflûÊÊ. At 0K, Germanium behaves as. (A) a conductor (B) an intrinsic semiconductor (C) an insulator (D) an extrinsic semiconductor 0K U apple ÁŸÿ ÿfl Ê U UÃÊ Ò (A) øê Ë Ã U (B) ŸÒ œ øê Ë Ã U (C) ÁfllÈà UÊappleœË Ë Ã U (D) Ês œ øê Ë Ã U!5/OSS/-3-A! [ Contd...
3. Which one of the following electromagnetic radiations is most energetic? (A) Ultraviolet radiations (B) X-rays (C) Infrared radiations (D) Light rays ÁŸêŸÁ Áπà apple ÊÒŸ- Ê ÁfllÈÃøÈê Ëÿ ÁflÁ UáÊ flê Áœ Ê flêÿ Ò? (A) UÊ Ò ªŸË ÁflÁ UáÊ (B) Ä Á UáÊapple (C) fl UÄà ÁflÁ UáÊ (D) Ê Ê Á UáÊapple. When the space between the plates of a capacitor having air is filled with a material of dielectric constant 6, its capacitance becomes : (A) 6 times (B) (C) 36 times (D) 6 times 36 times Á Ë flêÿè-ÿèäã œêá UòÊ Ë å apple UÊapple apple Ëø apple SÕÊŸ Êapple 6 UÊflÒlÈÃÊ apple ŒÊÕ apple UÊ ÊÃÊ Ò ÃÊapple ß Ë œêá UÃÊ Êapple ÊÃË Ò (A) 6 ªÈŸË (B) (C) 36 ªÈŸË (D) 6 ªÈŸË 36 ªÈŸË 5. The number of electrons and neutrons in 8 8O atom are respectively : (A) 8 and 8 (B) 8 and 0 (C) 0 and 8 (D) 0 and 8 8 8 O U ÊáÊÈ apple ß appleä UÊÚŸÊapple ÊÒ U ãÿí UÊÚŸÊapple Ë ÅÿÊ Ê (A) 8 ÊÒ U 8 Ò (B) 8 ÊÒ U 0 Ò (C) 0 ÊÒ U 8 Ò (D) 0 ÊÒ U 8 Ò 6. Which one of the following semiconductor devices does not need any reverse bias for its operation? (A) Zener diode (B) LED (C) Photodiode (D) Solar cell ÁŸêŸÁ Áπà apple apple Á œ øê ÿèáäã Êapple Ÿapple Êÿ ÁŸc ÊŒŸ apple Á à Á ŸÁÃ Ë Êfl ÿ ÃÊ Ÿ Ë ÊappleÃË? (A) appleÿ U «UÊÿÊapple«U (B).ß.«UË. (C)» Êapple UÊapple«UÊÿÊapple«(D) ÊÒ U apple 3!5/OSS/-3-A! [ Contd...
7. The orientation of an electric dipole in a uniform electric field which corresponds to its stable equilibrium is : ÊŸ ÁfllÈà ˇÊappleòÊ apple Uπapple ÁfllÈà Ámœ Èfl Ê SÕÊß ÃÈ Ÿ apple ªÃ ÁflãÿÊ Ò (A) (B) (C) (D) 8. The reaction responsible for energy generation in the Sun is : (A) a chemical reaction (B) a controlled fission reaction (C) an uncontrolled fission reaction (D) fusion reaction Íÿ apple Ê ŸŸ apple Á ûê UŒÊÿË Á Á ÿê Ò (A) UÊ ÊÿÁŸ Á Á ÿê (B) ÁŸÿ ÁòÊà ŸÊÁ Ëÿ Áflπ «UŸ Á Á ÿê (C) ÁŸÿ ÁòÊà ŸÊÁ Ëÿ Áflπ «UŸ Á Á ÿê (D) ÿÿ Á Á ÿê 9. The current gain of a transistor in common base configuration is 0.95. Its current gain in common emitter configuration would be : (A) 0.95 (B) 95 (C) 9 (D) ÿáÿc U- ÊœÊ U ÁflãÿÊ apple Á Ë UÊ Á S U U Ë œê UÊ Áéœ 0.95 Ò ÿáÿc U à ÁflãÿÊ apple ß Ë œê UÊ Áéœ ÊappleªË (A) 0.95 (B) 95 (C) 9 (D) 9 9 0. The combination of gates shown below represents : (A) AND gate (B) OR gate (C) NOT gate (D) NOR gate ŸËøapple Œ ÊÊ ÿê ªÿÊ ªapple U- ÿêapple Ÿ ÁŸM Á à UÃÊ Ò (A) AND ªapple U (B) OR ªapple U (C) NOT ªapple U (D) NOR ªapple U!5/OSS/-3-A! [ Contd...
. Mention two ways by which the strength of a given electromagnet can be increased. apple apple ŒÊapple à UË Êapple Ê À appleπ ËÁ Á Ÿ apple mê UÊ Á Ë ÁŒ ª ÁfllÈà øèê Ë ÃÊ apple flîáh Ë Ê ÃË Ò. Bodies A and B having masses m and m (m > m ) respectively have same linear momentum. Which of the two is moving faster? Explain your answer with relevant mathematical relations. Á «U A ÊÒ U B, Á Ÿ apple Œ ÿ ÊŸ Ê m fl m Ò, (m > m ), ÊŸ flappleª apple ªÁà ʟ Ò ßŸ apple apple Á Á «U Ê flappleª Áœ Ò? Ÿapple ûê U Ë ÿêåÿê ªÃ ªÁáÊÃËÿ ÿ mê UÊ ËÁ 3. The speed of sound in air is 33 ms at 0 C. Calculate its speed at 0 C. 0 C U flêÿè apple äfláÿ Ë øê 33 ms Ò 0 C U ß Ë øê Ê Á U Ÿ ËÁ. In the given circuit, no current is flowing through 00 Ω resistor. Calculate the value of R. Show relevant mathematical steps. ÁŒ ª ÁfllÈà Á U Õ apple, 00 Ω Áà UÊappleœ apple Êappleß œê UÊ flêá à Ÿ Ë Êapple U Ë Ò R Ê ÊŸ Á U Á à ËÁ Êfl ÿ ªÁáÊÃËÿ Á U Ÿ ø UáÊ Œ ÊÊ ß 5. When radiations of frequency 5.6 0 Hz are incident on a material, photoelectrons are released from it with zero kinetic energy. Calculate the work function of the material. (Planck constant =6.6 0 3 JS) Á Ë ŒÊÕ U 5.6 0 Hz ÊflÎÁûÊ apple Áfl UáÊ Ê ÁÃà ÊappleÃapple Ò ÃÊapple apple» Êapple UÊappleß appleä UÊÚŸ ÊÍãÿ ªÁÃ Ê apple Áfl ÈÄà ÊappleÃapple Ò ŒÊÕ apple Êÿ» Ÿ Ê Á U Ÿ ËÁ (å Ê ÁŸÿÃÊ =6.6 0 3 JS) 6. What is meant by directional characterstics of a p-n junction? Give its one application based on this characteristic. p-n Áœ «UÊÿÊapple«U apple ŒÒÁ Ê Á ˇÊáÊÊapple apple ÄÿÊ Á Êÿ Ò? ß Á ˇÊáÊ U ÊœÊÁ UÃ ß Ê ŸÈ ÿêappleª ÃÊß 5!5/OSS/-3-A! [ Contd...
7. In a tube of the shape shown in figure, a non-viscous fluid is in continuous, streamlined flow. Out of points A, B and C at which point will the pressure be minimum and why? ÁøòÊ apple Œ ÊÊ ß ªß ŸÁ Ê apple apple ÿêÿ à U Ãà ŸÈ UÒÁπ flê apple Ò A, B ÊÒ U C apple apple Á Á ŒÈ U à U Ê ŒÊ ãÿíÿã Ò? ÊÒ U ÄÿÊapple? 8. A heat engine operates between 0 C and 80 C. Calculate maximum possible efficiency of this engine. Êappleß c Ê ßã Ÿ 0 C ÃÕÊ 80 C apple Ëø Á à ÊappleÃÊ Ò, ß Ë Áœ à ÊÁflà ŒˇÊÃÊ Ê Á U Ÿ ËÁ 9. An open pipe of length l and a closed pipe of length l both resonate with the same tuning fork in their fundamental mode of vibration. Calculate the value of l /l. l ê Êß Ê πè Ê Êß ÃÕÊ l ê Êß Ê ãœ Êß Ë Ám È SflÁ UòÊ apple ÊÕ ŸË Í ê Ÿ flsõê apple ŸÈŸÊÁŒÃ Ò l /l apple ÊŸ Ê Á U Ÿ ËÁ 0. Indicating the meaning of the symbols used, write mathematical expression for Raynold number. How does its value determine the nature of flow of a fluid? Show that Raynold number is a pure number having no dimensions. ÿèäã apple ÃÊapple apple Õ ÃÊÃapple È appleuÿêúà«u ÅÿÊ apple Á ÿü Á Áπ ÿ ÅÿÊ Á Ë Ã U Ë flê Î ÁÃ Ê ÁŸœÊ UáÊ Ò apple UÃË Ò? Œ ÊÊ ß Á appleuÿêúà«u ÅÿÊ ÊÈh ÅÿÊ Ò ÊÒ U ß Ë Êappleß Áfl Ê Ÿ Ë ÊappleÃË. What is meant by the statement. Internal energy is a function of state. Will the internal energy of a system increase or decrease when work is done on it. Write the mathematical statement for first law of the thermodynamics. Write the convention used for determination of sign of work done in this expression. ÕŸ, Ê ÃÁ U Ê flsõê» Ÿ Ò apple ÄÿÊ ÃÊà ÿ ÊappleÃÊ Ò? Á Ë ÁŸ Êÿ U Êappleß Êÿ Á ÿê ÊÃÊ Ò ÃÊapple Ë Ê ÃÁ U Ê apple flîáh ÊappleÃË Ò ÿê Ë ÊÃË Ò c ʪÁÃ Ë apple Õ ÁŸÿ Ê ªÁáÊÃËÿ ÕŸ Á Áπ ß ÿü apple Êÿ Ê Áø Ÿ ÁŸœÊ Á Uà UŸapple apple œ apple Á U Ê UË Ê À appleπ ËÁ. Explain the principle, construction and working of a cyclotron with the help of a labelled diagram. ŸÊ Ê Á Ã Ê appleuπ Ë ÊÿÃÊ apple ÊßÄ Êapple UÊappleŸ Ê Á hê Ã, UøŸÊ ÊÒ U Êÿ ÁflÁœ ÊÊß OR / ÕflÊ Explain the principle, construction and working of a moving coil galvanometer with the help of a labelled diagram. ŸÊ Ê Á à ÁøòÊ Ë ÊÿÃÊ apple ø È «U œê UÊ Ê Ë Ê Á hê Ã, UøŸÊ ÊÒ U Êÿ ÁflÁœ ÊÊß 6!5/OSS/-3-A! [ Contd...
3. With the help of a diagram, describe the set up of Young s double slit experiment. Write conditions for the formation of bright and dark fringes in terms of (i) path difference phase difference. ÁøòÊ Ë ÊÿÃÊ apple ÿ ª apple ÁmÁ Ê UË ÿêappleª ÿflsõê Ê fláê Ÿ ËÁ ŒËåà ÊÒ U ŒËåà Á» ÁŸ Ê áê Ë ÊÃappleZ (i) Õ- ãã U Ê- ãã U apple ŒÊapple apple Á Áπ. Using Bohr s model of hydrogen atom, derive mathematically that the energy of the electron in its n th 3.6 orbit is given by E n = ev. n Êapple U apple Êß«UÊapple Ÿ U ÊáÊÈ ÊÚ«U Ê ÿêappleª U apple ªÁáÊÃËÿ M apple ÿèà ÛÊ ËÁ Á ß appleä UÊÚŸ Ë ß Ë 3.6 n flë ˇÊÊ apple Ê E n = ev ÊappleÃË Ò n 5. What are energy bands in solids? How are these formed? How do we classify solids as conductors and semiconductors on the basis of energy band diagram? UÊapple Êapple apple Ê - Ò «U ÄÿÊ ÊappleÃapple Ò? flapple Ò apple ÁŸÁ à ÊappleÃapple Ò? Ê - Ò «UÊapple apple ÊœÊ U U UÊapple Êapple Ê flªë UáÊ øê ÊÒ U œ øê apple M apple Á Ê U UÃapple Ò? 6. Explain why : (i) Sky appears blue when viewed from earth. Sun appears red at the time of Sunrise and Sunset. ÿêåÿê ËÁ Á ÄÿÊapple (i) ÎâflË apple ŒappleπŸapple U Ê Ê Ê ŸË Ê Ÿ U ÊÃÊ Ò ÍÿÊapple Œÿ fl ÍÿÊ Sà apple ÿ Íÿ Ê Ÿ U ÊÃÊ Ò 7. State the three laws of motion. Use the first law to define force and inertia and the second law to define acceleration. ªÁà apple ÃËŸ ÁŸÿ Á Áπ apple ÁŸÿ Ê ÿêappleª U apple fl «Uûfl Êapple ÃÕÊ ÁmÃËÿ ÁŸÿ Ê ÿêappleª U apple àfl UáÊ Êapple Á U ÊÁ à ËÁ 8. What is Electromagnetic Inductions? State Faraday s law of Electromagnetic Induction. Express second law in mathematical form. Name and state the law used for determination of direction of induced emf. ÁfllÈÃ-øÈê Ëÿ apple UáÊ ÄÿÊ ÊappleÃÊ Ò? ÁfllÈÃ-øÈê Ëÿ apple UáÊ œë»ò UÊ«appleU Ê ÁŸÿ Á Áπ ÁmÃËÿ ÁŸÿ apple Á ªÁáÊÃËÿ ÿ Ë Á Áπ appleá Uà emf Ë ÁŒ ÊÊ ÃÊŸapple apple Á ÿèäã ÁŸÿ Ê ŸÊ ÃÕÊ ÕŸ Á Áπ 6 6 7!5/OSS/-3-A! [ Contd...
9. Drawing a neat labelled diagram, show the refraction of a ray of light passing through a prism of equiangular triangle base. How does the value of angle of deviation change as we increase the value of angle of incidence? Draw the corresponding graph. If deviation is minimum for an angle of incidence of 5, calculate the value of (i) angle of minimum deviation refractive index of the material of the prism. Sflë U ŸÊ Ê Á Ã Ê appleuπ ŸÊ U ÁòÊ È ÊœÊ U apple Á í apple apple Êapple U Ê Ê Ë Á UáÊ Ê flã Ÿ Œ ÊÊ ß Ê ÃŸ ÊappleáÊ ÊŸapple apple Áflø Ÿ ÊappleáÊ Á Ê U ÊÁflà ÊappleÃÊ Ò? ªÃ ª Ê» ŸÊß ÿáœ Ê ÃŸ ÊappleáÊ 5 apple ªÃ Áflø Ÿ ÊappleáÊ ãÿíÿã Êapple ÃÊapple (i) ãÿíÿã Áflø Ÿ ÊappleáÊ Á í apple ŒÊÕ Ê flã ŸÊ Ê Á U Ÿ ËÁ 6 30. In a hydroelectric power plant, water falls from a height of 5 m. If the quantity of water falling per second be 0 8 kg, calculate : (i) (iii) The work done by the falling water at the base of the dam. Power generated by the plant under ideal conditions. The useful electrical power available when the generator is 90% efficient. Á Ë ÁfllÈà ÿ òê apple 5 m Ë øêß apple ŸËøapple Áª UÃÊ Ò ÿᜠs apple ŸËøapple Áª UŸappleflÊ apple Ê Á ÊáÊ 0 8 kg Êapple ÃÊapple Á U Á à ËÁ (i) «ÒU apple ÊœÊ U U Áª UŸappleflÊ apple ß mê UÊ Á ÿê ªÿÊ Êÿ ÊŒ Ê Œ ÊÊ Êapple apple ß ÿ òê mê UÊ ÁŸÃ Ë Ê Ÿapple flê Ë ÊÁÄà (iii) ÿᜠÁŸòÊ Ë ŒˇÊÃÊ 90% Êapple ÃÊapple éœ ÿêappleíÿ ÁfllÈà ÊÁÄà OR / ÕflÊ A body of mass 0 kg is moving on a rough level plane with a constant speed of ms. (i) How many minimum number of forces are acting on it? Explain your answer. If a force of 0 N is now applied on the body for s in the direction of motion, calculate its speed after s. (iii) How much distance will it travel in these two seconds? 0 kg Œ ÿ ÊŸ Ê Á «U Á Ë πè UŒ UË, à à U ms Ë ø U øê apple ªÁà ʟ Ò (i) ß U ªŸapple flê apple Êapple Ë ãÿíÿã ÅÿÊ ÄÿÊ Ò? Ÿapple ûê U Ë ÿêåÿê ËÁ ÿáœ ß Á «U U 0 N Ê ªÁÃ Ë ÁŒ ÊÊ apple ªÊÿÊ Ê ÃÊapple s øêã ß Ë øê Ê Á U Ÿ ËÁ (iii) ߟ ŒÊapple apple «U apple ÿ Á «U Á ÃŸË ŒÍ UË Ãÿ appleuªê? 6 - o O o - 8!5/OSS/-3-A! [ Contd...