1. What is reverberation? [1]
2. Give reason why, a block of plastic when released under water comes up to the surface of water.[1] 3. (a) Define relative density.(b) Relative density of silver in 10.8. The density of water is 103 kg/ m. What is the density of silver in SI unit? 4. State two main postulates of Thomson’s model of an atom.[2] 5. (a)Calculate the number of molecules in 8 g of O2 (b)Calculate the number of moles is 52 gas of He (Helium) [At. mass: O = 16 u,He = 4 u] 6.(a) Define 1 watt.(b) An electric bulb of 60 W (sixty watt) is used for 6 (six) hours per day. Calculate the units of energy consumed in one day by the bulb. [2] 7. (a)What are polyatomic ions ? b) Write the formulae and names of the compounds formed by combination of (i)Fe3+ and SO4-2 (ii)NH41+ and Co3-2 8. Define valency of an element. Find the valency of chlorine and Magnesium (At. No. Of Chlorine= 17, Magnesium =12) 9. Explain how human ear works in the transmission of sound wave to the brain. [3] 10.(a)Define potential energy. Write an expression for potential energy of an object of mass m raised through a height h.(b) Find the energy possessed by an object of mass 10 kg when it is raised to a height of six meter above the ground given g = 9.8 m/s2. 11. Define frequency, amplitude and speed of a sound wave.[3] 12. (a) State the drawbacks of Rutherford’s model of the atom ? Explain the suggestions put forward by Neils Bohr in his model of atom to overcome these drawbacks. (b) Define isotopes with one example. Write two applications of isotopes.[5] 13.(a)Write the name of the sub - atomic particle discovered by J. Chadwick. What type of charge occurs on this particle? In which part of atom this particle is located? (b)List three steps of experiment performed by Rutherford for his model of an atom. (c)Define isobars, write its one example. (d)Which scientist concluded that size of nucleus is very small as compared to size of an atom ? [5] Or, (a) Write chemical formula of Potassium Sulphate. (b)Calculate the molar mass of : (i)Ethyne (C2H2) and (ii)Phosphorous molecule (P4) (Atomic mass of C = 12u, H=1u and P =31u). 14. (a) State Law of conservation of energy. Explain it with one example.(b) Two girls each of weight 400 N (Four hundred N) climb up a rope through a height of 8 meters (eight meters). Girl A takes 20 (Twenty) seconds while Girl B takes Fifty seconds to accomplish this task. What is the power expended by each girl ? (c)An electric heater is rated 1500 watt. How much energy does it uses in 10 hours (ten hours) ? [5] 15.(a)Define work done by a constant force on an object. Write an expression also for the work done. (b)How much work will be done on an object by a force if the displacement of the object is zero ? (c) What is the kinetic energy of an object? Write an expression for the kinetic energy of an object of mass m moving with a speed v.[5] OR, State law of conservation of energy. An object of mass 10kg is dropped from a height 5m above the ground. Show that total energy of the object at the height 5m and 2m is same. (Take g = 10m/s2). What happens to the energy when the object touches the ground? 16. In the wave motion of a string, every particle:- (a)Rotates (b) Oscillates (c) is stationary (d) displaces from one end to another. 17. The wave produced in the interior of the earth is called:- (a)Longitudinal (b) Seismic wave (c) Sound wave (d) Transverse wave 18. We can sense a compression is a slinky if :- (a) Turns are close to each other (b) Neither turns are close nor far away (c)Turns are far away (d) None of these. 19. Up thrust depends upon :- (a)volume (b)density (c)‘g’ (d)All of these 20. When all ice floating in water melts the level of water in Container:- (a)Falls (b) Rises (c)remains unchanged (d) None of these 21.Mass of an object in air is 40 kg. Mass of this object in water will be :- (a)More than 40 kg (b)Less than 40 kg (c)40 kg (d)Zero 22. Which of the following has the highest density? (a)Alcohol (b) Glycerin (c) Water (d) Sea water Science Class 9 Standard Question Papers 2012-13 -as per the latest Exam Syllabus ix_science_sample_paper-SA-2-1 Download File ix_science_sample_paper SA-2-2 Download File ix_science_sample_paper-SA-2-3 Download File ix_science_sample_pape - SA-2-4 Download File ix_science_sample_pape_SA-2-5 Download File
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Floatation+Sound+Work and Energy
Floatation: 1. Seema purchased a new pair of high heeled fashionable shoes. During a picnic organized by her school Seema intentionally wore these high heeled shoes for showing off to her classmates. However, Seema could not walk as comfortably as her classmates during the picnic. After walking through some distance she felt tired. Her friend Hema held her hand firmly and helped her in walking. Later on, Hema advised Seema to wear shoes of flat sole on such a trip. Seema Bought flat shoes and now she felt more comfortable while walking. a) Why Seema could not walk properly and comfortably during her school picnic? b) A girl weighing 400N wear high heel shoes. If she stands on one foot only and the area of heel be 5cm2, what pressure is acting on the heel? c) What value was shown by Hema? 2. Raman lived in a village situated in a hilly area. There was a beautiful lake near the village. During vacations Raman usually went to visit around the lake. Sometimes he used to sit just near the bank of lake with his legs immersed in lake water. Raman observed that it is easier to raise or move his legs inside water than in air. He could not understand the cause of it. He asked his elder brother Mohan. Mohan told him that it is due to force of buoyancy in accordance with Archimede’s principle. Mohan explained the principle in detail to Raman. Now Raman was happy as he knew the exact explanation of his observation. a) In your opinion what is buoyant force? Under which condition does it act? b) State Archimede’s principle. c) What quality was shown by Raman? What quality was shown by Mohan? 3. Once Sanya and her brother Satvik went to Chandigarh to spend their holidays with their uncle’s family. One day Sanya, Satvik and their cousins visited Sukhna lake. They found that motor boats are available. They decided to have a boat ride in Sukhna lake. They were provided special jackets and were asked to wear the jackets before going on to the boat. Young Satvik could not understand the purpose of wearing the special jacket over and above his normal clothing. Sanya’s cousin brother Abhishek, who was a student of class X, knew the function of jacket. He said that the jacket is a life saving jacket and explained its working principle. Now Satvik was assured of his safety and wore the jacket. They had a happily boat riding in Sukhna lake for one hour. a) What is the fuction of air filled life saving jacket and how does it work? b) What were the doubts of Satvik? How did Abhishek clear these doubts? c) State the law of Floatation. 4. Sita and Radha were close friends and both were students of 8th standard in same school. Sita felt burdened while carrying her school bag in her hand or on her shoulders. She also observed that it was easier to carry Radha’s school bag, although it was as heavy as it was her own. He could not know the reason for this anomly and daily felt pain in her shoulders while carrying her school bag. Radha told her the difference. While strap of Radha’s school bag was broad and thick, the strap of Sita’s bag was made of thin and strong string. Radha presented a new schoolbag having a broad and thick strap to Sita. When Sita used that bag she did not feel any burden in carrying her school bag. Now she was happy and satisfied. a)Why is it difficult to hold a school bag having a strap made of a thin and strong string? b) Define pressure and give its SI unit. c) What value was shown by Radha? (WORK AND ENERGY) 1. An old man was waiting for a roadways bus at a bus stand with his heavy luggage bag in his hands, He was tiring and used to shift the bag from one hand to another and so on. Shashank was seeing this. He felt uneasy and requested the old man to put his bag on the floor of bus stand near him so that he may be free. Initially the old man looked suspiciously towards Shashank but on persuation he agreed and put his heavy bag on the floor and carefully set on it. Now he was relieved and peaceful. a) Was the old man applying some force while holding the bag in his hand? If yes, of what type? b) Was the old man doing some work while holding the bag in his hand? Why? c) What value was shown by Shashank? 2. On a Sunday evening Anamika was preparing a chart for a science project in her room. Her mother asked Anamika to help her in kitchen but Anamika said that she was too busy and doing a very important work. By the time Anamika completed her chart, she felt tired and hungry. She took her dinner and went to bed. a) Was Anamika actually doing work from physics point of view? Give reason. b) What type of work was Anamika doing? c) Why did she felt tired and hungry? d) What quality was displayed by Anamika? 3. There was a bad habit in Gopal’s family. Nobody used to switch off electric bulbs/tubes/fans etc., even when not being required. Due to this they have to pay a huge amount as the electricity bill per month. Gopal’s physics teacher explained in the class the importance of energy savings. He gave an example that a CFL lamp of 18W rated power almost gives same light as a 100W incandescent bulb but saves energy. Gopal requested all his family members about energy savings. They used to switch in electrical appliances only when needed. They also replaced bulbs with CFLs. Next month the amount of electricity bill of their house was quite less than it used to be earlier. Now they all acknowledged the importance of energy saving. a) What is power? What is its SI unit? b) In which unit the electric energy consumed is measured? What is its value in joules? c) What should we try to save consumption of energy? d) What value was shown by Gopal? What was the result of his efforts? 4. Rajni was swinging on a swing in her society park. She wanted to increase the speed of the swing. She started pushing the ground backward harder with her feet, when her swing was at its lowest position during its oscillations. She enjoyed it but did not show the actual mechanism. Her elder brother Ajay told her the actual mechanism of gaining speed in a swing. a) What type of energy was possessed by Rajni while swinging on a swing? On what factors does it depend? b) Why did the swing speed increased when Rajni pushed back the ground harder? c) What conclusion do you draw about the characteristic quality of Rajni from the above? VALUE BASED QUESTIONS (SOUND) 1. Rajesh went to a hill station with his parents and elder sister Shashi. He was experiencing the scenic beauty of a hill station for the first time. One day they were walking in a forest area, Rajesh loudly called”Shashi, Shashi didi “and so on. To his surprise he could distinctly hear the same sound twice. He thought that somebody is present in the forest area who is mimicking his voice. He started weeping. Hearing her weeping sound Shashi came near him, consoled him and explained the true cause of repetition of sound and told him that the phenomenon is called echo. Rajesh was satisfied now. When they returned to their hotel room, Rajesh shouted loudly in the hotel room but now there was no echo. a) What is echo? How is it formed? b) Why did not Rajesh hear any echo in his hotel room? c) What value was shown by Shashi, the sister of Rajesh? d) A person speaks in front of a huge building and hears an echo exactly 2 s afterwards. What is the distance of the building from the person? Speed of sound=340m/s. 2. Ravi and Vikas were feeling bored during a vacation. Vikas had an idea. He asked Ravi to prepare a toy telephone set. They took two small size plastic glasses and a long thread. Using a needle, they drilled small holes in two glasses and tied the ends of thread to two glasses by passing the thread through the holes. Now they stood apart with one plastic glass with Ravi and the other with Vikas. Ravi spoke softly in to his plastic glass and vikas was able to clearly listen the sound. Then Vikas answered softly in his plastic glass and Ravi could listen the message. Now both of them were happy. They showed their telephone set to their friends too. a) How the sound was travelling from one end of thread to another? Explain the mechanism. b) How is sound produced? Can sound travel through vacuum? c) What quality was exhibited by Vikas and Ravi? 3. Swati lived in her apartment situated on the 4th floor of a multistory building in Gurgaon. One day she observed from the window of her room that a bansuri made of bamboo reed. She started playing with it. She found that if one blows gently at the mouth of Bansuri, the sound produced was soft but when blown with more power, the sound produced was a loud sound. Using her fingers she closed all the holes of Bansuri and blew at its mouth and found the sound to be a low pitched sound. However, when she opened different holes by removing fingers from the holes. She found the sound to be a sharp, high pitched sound. She asked her father, why it is so. Her father explained the detailed mechanism of production of sound waves in air to her. a) What type of waves is produced in the air column of Bansuri? b) What is the difference between a soft sound and a loud sound? c) What is the difference between a low pitched sound and a high pitched sound? d) What quality was shown by Swati? 4. Narender studies in class VII. Once he was suffering with cold and cough and was running high temperature. His mother took him to a doctor. The doctor examined the chest and back of Narender with the help of a device ‘stethoscope’. While examining with stethoscope doctor asked Narender to take longer breathings. After examining Narender the doctor prescribed some drugs. By regular use of these drugs Narender was normal within four days. But he could not understand the purpose of being examined by the use of stethoscope. During winter break his cousin Mukesh, who was studying in a medical college, visited their place. On the request of Narender, Mukesh explained to him the exact purpose of stethoscope and its action. a) What is stethoscope? What is its use? b) How does a stethoscope work? c) Name two other devices which work on the principle as being utilized in a stethoscope? d) What quality was shown by Narender and what by Mukesh? Thanks to : Source:davpushpanjali 1. Define 1 W of power. [1]
2. When is work done by a force zero.[1] 3. (a) Differentiate between upthrust and weight(b)When does an object float or sink.[2] 4. A truck and a car are running with same velocity. Which of the two has less kinetic energy ?[2] 5. A rock that is falling from the top a cliff into the river. The weight of the rock is 750 N. The acceleration of free fall is 10 m/s2. Calculate its kinetic energy just before hitting the water 6. Write any three difference between Transverse and longitudinal Wave?[3] 7. (a) State a condition for an echo to be heard.(b)Bats cannot see then how do they catch their Prey.[1+2] 8.(a) Derive expression of frequency, wavelength and Velocity of wave . (b) A sound wave travels at a speed of 339 m/s ‘ if the wavelength is 1.2 cm, what is the frequency of the wave.[3] 9.A student wishes to work out how much power she uses to lift her body when climbing a flight of stairs. Her body mass is 60 kg and the vertical height of the stairs is 3.0 m. She takes 12 s to walk up the stairs. (a) Calculate: (i) The work done in raising her body mass as she climbs the stairs,(ii) The output power she develops when raising her body mass. (b) At the top of the stairs she has gravitational potential energy. Describe the energy transformations taking place as she walks back down the stairs and stops at the bottom. (c) What is the difference between a gravitational potential energy and kinetic energy?[5] 10. Write the full name of sonar. How will you determine the depth of a sea using echo ranging? (b) A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.[5] Or, (a) what is meant by intensity of sound? (b) Mention the conditions for an echo to be heard clearly. (c) A ball is dropped into a pond from a height of 44.1 m. The splash of sound is heard 3.13 second after the ball is dropped. Determine the velocity of sound in air. [5] Download solved paper 9th Solved Science SA-2 Sample paper-1 9th Solved Science SA-2 Sample paper-2 9th Solved Science SA-2 Sample paper-3 9th Solved Science SA-2 Sample paper-4 Download File Solve Sample paper [Biology]Summative Assessment–II: Paper-2
1. How do children in many parts of India get immune to hepatitis A by the time they are 5 years old? [1] Ans. The vaccine of hepatitis A is given to the children below 5 years of age to produce immunity against hepatitis A. 2. (a) A flowering plant whose embryo possesses single cotyledon (Give scientific term). (b) A unicellular, eukaryotic aquatic organism (Name the kingdom) [1] Ans. (a) Monocotyledonous plants (seeds with one cotyledon) (b) kingdom Protista 3. Why are we normally advised to take bland and nourishing food when we are sick?[2] Ans. When we are sick, our normal body functioning is disturbed. During that period, if we take bland and nourshing food, it helps in digestion and absorption by the body. 4. Why are antibiotics effective against bacteria but not against viruses? [2] Ans. Antibiotics are effective against living organism like bacteria while the viruses are DNA fragments, not a living organism. Hence, viruses cannot be killed by any antibiotic. 5. (a) Give one characteristic difference between primitive and advanced organisms. (b) Name the phylum to which the following are included. (i) Spider (ii) Cockroach (iii) Prawn (iv) Housefly[2] Ans: (a) The activities of life are performed by a single cell in primitive organisms while there are different organs for performing various functions in advanced organisms. (b) (i) Spider – Arachnida (ii) Cockroach – Dictyoptera (iii) Prawn – Arthropoda (iv) Housefly – Arthropoda 6. List three ways to control soil pollution. [3] Ans. (i) Proper drainage and sewer system in densely populated areas, so that they do not go in open for defaecation. (ii) Less use of chemicals in the form of fertilizers, pesticides, weedicides, etc. (iii)Proper disposal of non-degradable waste materials such as plastic carry bags, glass bottles, electronic wastes, etc. 7. "The flow of energy is unidirectional whereas the biogeochemical transfer is cyclic". Explain why?[3] Ans: Energy transfer is said to be unidirectional because when the energy is absorbed by autotrophs from the sun, it is never reabsorbed by it. Similarly when consumers eat up the producers directly or indirectly the energy transferred in this process can never be reversed in the food chain. On the other hand in biogeochemical cycles are those through which chemical elements move from environment to organism and back to the environment. Hence, they are never lost. 8. Give cause and remedy of : (a) Hepatitis (b) AIDS (c) Malaria [3] Ans. (a) Hepatitis : It is a serious disease caused by hepatitis virus. Vaccines for Hepatitis A and Hepatitis B should be taken. (b) AIDS — It is caused by a virus (HIV), Human Immunodeficiency Virus. Avoid the transfer of HIV positive blood . (c) Malaria — It is spread by female Anopheles mosquito Quinine is a medicine for malaria treatment. It is obtained from a tree. 9. (i) Make neat and labelled sketch of Nitrogen cycle in nature. (ii) Describe in brief the role of Nitrogen fixing bacteria and of lightening in fixing atmospheric nitrogen.[5] Ans: Make neat and labelled sketch of Nitrogen cycle in nature. Certain bacteria and blue-green algae can fix atmospheric nitrogen directly into nitrates. The nitrogen-fixing bacteria can be free-living, like Azotobacter and Clostridium, or symbiotic bacteria (Rhizobium). Rhizobium is found in the root nodules of certain leguminous plants, like peas and beans 10. What is immunization? Name any four diseases which can be prevented by immunization. [5] Ans. Immunisation is a specific method for preventing diseases. Immunisation protects the body by either helping it to create new antibodies by presenting part or whole of the disease–causing agent to the person's immune system, a long term approach or by providing it with active antibodies, a temporary solution. Polio, tuberculosis, measles, tetanus, etc. are the diseases which can be prevented by immunization. Searches related to solved sample paper of 9th class sample paper of science class 9th Click Here Solve Sample paper [ 9th Biology] Download /View Q. What is an antibiotic? Give its one example Ans: Antibiotic is a chemical substance that kill bacteria, secreted by microorganisms which can kill the pathogens Example – Penicillin Q. (i) Which disease is more harmful : Acute or Chronic disease ? Why? (ii) Why are we advised to take bland and nourishing food when we are sick? Ans: (i) Chronic disease Because chronic diseases have drastic long term effects on people’s health as compared to acute disease (ii) (a) Such food does not contain oil or fat and spices so it is digested easily (b) It provides sufficient energy for recovery after the disease (c) It provides adequate amount of nutrients required for regeneration of cells and tissues. Q. (i) How atmospheric inert nitrogen gas is converted into usable nitrogenous form for the various life forms? (ii) Draw a labelled diagram to show nitrogen cycle in nature Ans: (i) (i) By the help of free living nitrogen fixing bacteria or nitrogen fixing bacteria found in roots of legumes. (b) Physical process : During lighting, the high temperatures and pressures created in the air convert nitrogen into oxides of nitrogen. These oxides dissolve in water to give nitric and nitrous acids and fall on land along with rain. Q. (i) What are the consequences of Global warming (ii) Why is water essential to life? Ans: (i) Rise in temperature (ii) Melting of glacier (ii) (a) All life processes require water. (b) Water is needed for transportation of substances from one part of body to other in dissolved farm. Q. Name the causal organism of AIDS. Why a person suffering from AIDS cannot fight even very minor infections ? Ans: HIV (virus) The virus goes to the immune system and damages its function. So the body can no longer fight off even minor infections. Q. Write the symptoms when following organs are targeted by microbes. (a) Lungs (b) Liver (c) Brain. Ans: Lungs – cough , breathlessness. Liver – Jaundice Brain – Headache, vomiting, fits Q. What is immunization? List two diseases against which vaccines are available. Ans: Immunization is the process in which a person's immune system is enhanced by giving inactive form of the disease causing agent ( immunogen). This agent develops the human immune system to fight against that agent and if attacked again by the same agent the immune systems give a more stronger response and eliminate the disease. Two diseases for which vaccines are available are Polio and Diphtheria. Q. Write the full form of AIDS. List four modes of transmission of virus of this disease. Ans: Aquired Immuno Deficiency Syndrome Modes of transmission of virus of this disease a) Through sexual contact b) Through blood trsnsfusion From mother to child c) Through infected needled or syringes Q. Health workers are exposed to more sick people than others in the community. Write any four preventive measures they take to avoid sickness. Ans: Preventive measures: (i) Hand washing after any direct contact with patients (ii) Wearing gloves while treating or examining the patient. (iii) Proper disposal or sterilizing the instruments. (iv) Immunisation. Q. Same drug does not work against the microbes belonging to different groups. Why? State the mechanism of antibiotics in killing bacteria. Ans: Every micro organism has its own biochemical cycle. So one type of antibiotic can stop or block biochemical cycle of one type of micro organism only but not all type of micro organisms. Antibiotic destroy the cell wall during the asexual reproduction cycle hence the bacteria can be easily killed. Q. “Water is essential for living organisms”. State two reasons to justify this statement. Ans: Water is needed by organisms to maintain their body temperature. Water is needed by organisms to perform many biochemical reactions. Q. List the names of three diseases caused by virus stating their mode of communication in each case. Ans: (1) Influenza (2) Hepatitis (3) AIDS Mode of communication (1) Blood transfusion (2) Unprotected sexual contact (3) Use of contaminated needles syringes etc. (4) From mother ‘to foetus thmyh’ placenta Q. List four preventive measures against communicable diseases. Ans: 1. Health education 2. Isolation 3. Proper sanitation 4. Sterilization of articles used by patients 5. Vaccination 6. Provision of safe water supply Q. A person has lost his power to fight infections. Name the disease the person is suffering from. State the pathogen and modes of transmission of this disease. Ans: Suffering from AIDS Name of pathogen is a virus known as HIV. Mode of transmission of HIV is : 1. Intimate sextual contact 2. Blood transfusions 3. Contaminated needles, syringes or razors (Any 2 points) Download CBSE Summative & Formative Assignment based on CCE Biology Term-2 Biology Science Ch-07. Diversity in Living Organisms Download File Biology Science Ch-13. Why do we fall ill Download File Biology Science Ch-14. Natural Resources Download File Download CBSE Summative & Formative Assignment based on CCE Test Paper Biology Term-2 CCE Test Paper Biology Chapter Natural Resources ix Biology-1 Download File CCE Test Paper Biology Chapter Natural Resources ix Biology-2 Download File Class IX Biology Chapter 7 : Diversity In Living Organisms NCERT Solutions Download File CCE Test Paper Biology Chapter 7 : Diversity In Living Organisms Solved Download File 9th_diversity_in_living_organization_study_notes. Download File Class IX Biology Chapter Chapter: Why do we fall ill? NCERT Solutions Download File CCE Test Paper Biology Chapter: Why do we fall ill? Solved Download File |
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