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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 44601. |
What is analogous organs? |
| Answer» Those organs which have different origin and different basic structural plan but have similar appearance and perform similar function are called analogous organs | |
| 44602. |
Working procedure of electric motor and generator |
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Answer» D.C. generator: A d.c. generator is a device which converts mechanical energy into electrical energy.D.C generator has split ring commutator instead of slip rings.Split ring commutator: It consists of two semicylindrical brass rings S1\xa0and S2\xa0rigidly attached to the two ends of the armature coil. As the armature coil rotates, the two split rings also rotate about the same axis of rotation.\xa0Fig. D.C. generatorWorking: Suppose initially the plane of the coil is horizontal. The split ring S1\xa0touches the brush B1\xa0and S2\xa0touches B2. When coil ABCD is rotated clockwise, magnetic field lines passing through it change. The arm AB moves upwards and arm CD moves downwards. According to Fleming’s right hand rule, the induced current in the armature coil flows in the direction ABCD. In the external circuit, current flows from B2\xa0to B1. As the coil crosses its vertical position, the split ring S1\xa0comes in contact with B2\xa0and S2\xa0with B1.\xa0The arm AB now moves downwards and arm CD moves upwards. The induced current in the armature flows along DCBA. But in the external circuit, the current still flows from B2\xa0to B1. Hence, a unidirectional current flows in the external circuit. Electric Motor\xa0operates on direct current obtained from a battery.\xa0Principle: An electric motor works on the principle that a current carrying conductor placed in a magnetic field experiences a force.\xa0\xa0\xa0Fig.\xa0An electric d.c.\xa0motorConstruction:\xa0An electric motor consists of the following main parts:1. Field magnet: It is a strong horse shoe type magnet with concave poles.2. Armature: It is a rectangular coil ABCD having a large number of turns of thin insulated copper wire wound over a soft iron core.\xa0The armature is placed between the poles of the field magnet and it can be rotated about an axis perpendicular to the magnetic field lines.\xa03. Split ring commutator: It consists of a cylindrical metal ring split into two halves S1and S2. The two ends A and D of the armature coil are connected to the split rings S1\xa0and S2\xa0respectively. As the coil rotates, the split rings also rotate about the same axis of rotation. The function of the split ring commutator is to reverse the direction of current in the coil after every half rotation.4. Brushes: Two graphite or flexible metal rods maintain a sliding contact with split rings S1\xa0and S2, alternately.5. Battery: A battery of few cells is connected to the brushes. The current from the battery flows to the armature coil through the brushes and the split rings.Working: Initially, suppose the plane of the coil is horizontal. The split ring S1\xa0touches the brush B1\xa0and split ring S2\xa0touches the brush B2. The current in coil flows in the direction ABCD from the source battery, as shown in Fig.(a).Clearly, the currents in arms AB and CD are in opposite directions. The force acting on arm AB pushes it downwards while the force acting on the arm CD pushes it upwards. Thus the armature coil alongwith the axle rotates anticlockwise. After half a rotation, as shown in Fig.(b), the\xa0split ring\xa0comes in contact with brush B2, and S2\xa0in contact with brush B1. Therefore, the current in the coil gets reversed and flows along the path DCBA. A device that reverses the direction of flow of current through a circuit is called commutator. Thus the arm AB is now pushed up and the arm CD is pushed down. Therefore, the coil and the axle rotate half a turn more in the same direction. The reversing of the current is repeated at each half rotation, giving rise to a continuous rotation of the coil and to the axle.Split ring acts as commutator in electric motors. Refer ncert book |
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| 44603. |
How you can say hydro power plant is conventionl source of energy ? |
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Answer» Non renewable hi bhai ncert book padho Hydropower is a renewable source of energy since, the water in the reserviors can be refilled each time by rainfall and the water an be reused to produced electricity.\xa0 |
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| 44604. |
Define the word: Digestion... |
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Answer» It starts with right hand and ends with left hand Digestion: The process of breaking down of food mechanically and chemically into simpler and\xa0absorbable form is called digestion. Rajiv this is know as emulsification Breaking down of large food particle to smaller the process of changing food in your stomach so that it can be used by the bodyआमाशय में शरीर के पोषण हेतु आहार के रूपांतरण की प्रक्रिया @diti |
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| 44605. |
Explain the phenomenon of scattering of light? |
| Answer» Very fine particles scatter mainly blue light while particles of larger size scatter light of longer wavelengths. If the scattering particles are large enough, the scattered light may appear white. Blue colour of the sky and reddening of sun at sunrise and sunset are some phenomena observed due to scattering of light @diti | |
| 44606. |
Write about digestive system in human body |
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Answer» Entire information about digestive system is given. You can mould it as per your requirement.Digestion:\xa0Digestion is the process by which food is broken down into simple absorbable substances. Digestion of food takes place in the digestive system. Digestive system is made up of alimentary canal and associated glands.Parts of alimentary canal:The mouth, oesophagus, stomach, small intestine and large intestine form the alimentary canal. It is also known as the digestive tract.Mouth\xa0is guarded by upper lip and lower lip. The process of taking in food through mouth is called as ingestion.Buccal cavity\xa0is the inner region of the mouth. It encloses teeth and tongue.Teeth are of different types namely, incisors, canines, premolars and molars.Incisors are used for biting food.Canines are sharp and pointed and are used to pierce or tear food.Premolars and molars are the principal grinders helping to chew and grind the food.Tongue is a muscular organ attached to the floor of the buccal cavity at the back. It helps in mixing of food with saliva and swallowing it. It also helps in tasting different types of food with the help of taste buds present on it. The buccal cavity leads into pharynx.Pharynx\xa0is at the back of buccal cavity. The pharynx is the common channel for food and air. When you swallow food, a flap-like valve called the epiglottis closes the windpipe. It prevents the entry of food particles into respiratory tract.Oesophagus\xa0also called as food pipe helps in conveying the food from buccal cavity to stomach. The oesophagus is also known as the gullet. It is about 25 centimetres long. Food inside the oesophagus reaches the stomach by peristalsis movements.Stomach\xa0is the widest part of the alimentary canal. It is a J-shaped muscular organ with stomach occurs with the help of digestive juice. Digestive juice comprises of hydrochloric acid, mucous and some enzymes.Small intestine\xa0is made up of three regions namely duodenum, jejunum and ileum. Partially digested food called the chyme from the stomach is received by the duodenum. Duodenum also receives bile form the liver, enzymes from pancreas and secretes some enzymes on its own. All these substances bring about digestion of food in the intestine. The inner walls of the small intestine have millions of small finger like projections called the villi. Villi increase the surface area for digestion as well as absorption of digested food by eight times.Large intestine\xa0comprises of colon and rectum. Undigested food is sent into large intestine. Water from the food is reabsorbed to a great extent in the large intestine. Undigested waste is stored in the rectum for defecation.**** is the opening of the alimentary canal to the exterior. This helps in the elimination of faeces by the process of egestion.Associated glands:\xa0These glands include salivary glands, gastric glands, intestinal glands, liver and pancreas.Salivary glands\xa0are present inside the buccal cavity. They secrete saliva. This saliva plays an important role in breaking down complex components like starch into simple sugars.Gastric glands\xa0present inside the stomach secrete gastric juice which helps in the digestion of food.Intestinal glands\xa0secrete various enzymes which aid in the process of digestion of food.Liver\xa0is the largest gland in our body. The liver secretes a yellowish green watery fluid called bile. It is temporarily stored in a sac called the gall bladder. Bile plays an important role in the digestion of fats. Bile is sent into duodenum through a narrow tube-like structure called the bile duct. Bile breaks the larger fat molecules into tiny droplets, thereby increasing their surface area, which helps in the digestion of fats easily.Pancreas\xa0is the mixed gland. It acts as a both endocrine and exocrine gland. The pancreas secretes the pancreatic juice that helps to digest carbohydrates, proteins and fats. The pancreatic juice converts carbohydrates into simple sugars and glucose, proteins into amino acids, and the lipids into fatty acids and glycerol. The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion. Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body. The process of digestion has many stages. @diti |
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| 44607. |
What is scum in hindi |
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Answer» Fain A dirty or unpleasant substance on the surface of the liquid is called scum... |
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| 44608. |
What is pH of our backyard.Elucidate |
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Answer» 5.5and7.5 backyard 5.5 and 7.5 ph backyard .I think.... |
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| 44609. |
What is presbyopia? What causes presbyopia? How is presbyopia corrected |
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Answer» Catarat=>unlike coloured eyes....Surgery =>adjust the Retina Correctness=>bifocal lens two lens...see far object => cancave lens upper power(-)...near by object =>canvex lens lower power(+).... presbyopia_ .........Reason of defect: gradual weakening of ciliary muscles, thereby decreasing the flexibility of the eye lens. Presbyopia is the defect of vision due to which an old person cannot see the nearby objects clearly due to loss of power of accommodation of the eye..... |
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| 44610. |
What is doubble circulation |
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Answer» Blood passes through the heart twice while completing 1 circulation , so it is called double circulation . flow of blood twice to complete one circulation called double circulation |
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| 44611. |
What do you mean by aperture? |
| Answer» Ok | |
| 44612. |
Fe does not burn on heating but iron filling burn vigorously why ? |
| Answer» Iron has a strong molecular force of attraction. Hence when heated it doesn\'t reach to its ignition temperature and doesn\'t burn. But iron fillings when sprinkled in flames attain the ignition temperature ( as iron fillings are comparatively smaller particles) and gain larger surface area for the reaction. Therefore they burn vigorously.......... | |
| 44613. |
What is different between ac current and dc current |
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Answer» Ac current can travel long distance but dc can\'t. Ac currrent can be stored but dc current can\'t Ac is alternating current bt dc is direct current...... AC is alternating current where the current changes the direction every second..It is used in generators.It converts mechanical energy to electrical energy.DC or direct current does not change direction every second.It is used in motors.It is used to convert electrical energy to mechanical energy........ Alternative and direct |
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| 44614. |
Why kerosene don\'t decolourised bromine water while cooking oil do ?? |
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Answer» Because cooking oil are unsaturated and kerosene oil are saturated carbon compounds Kerosene doesnot not decolourise bromine water while cooking oil does cuz cooking oil are unsaturated while kerosene are saturated carbon compound.unstaturated carbon chains are capable of decolourising bromine water while\xa0saturated carbon chain cannot decolourise bromine water. |
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| 44615. |
Structre of methane |
| Answer» Methane: CH4C=6=2,4H=1In the bonding\xa0of methane molecule, one atom of carbon shares four electron pair, one with each of te four atoms of hydrogen. | |
| 44616. |
Which act as anode in electrorefining of metals ?? |
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Answer» Same pure metal in less quantity. I have done chemistry for my exam u can ask any ques Same metal Impure metal |
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| 44617. |
What happens when sol.of Na2SO4 and BaCl2 are mixed |
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Answer» White precipitate BaSo4 formed NaCl2+Ba2So4 double displacement reaction This is double displacement reaction.the balanced equation isBaCl2\xa0+\xa0Na2SO4\xa0=\xa0BaSO4\xa0+\xa02NaClbacl2=barrium chloride.na2so4 =sodium sulphate Double displacement reaction will take place |
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| 44618. |
Why ammeter is connected in series |
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Answer» To measure maximum current in the circuit. Is this can be a reason that current passes same from all connection as we see potential difference is not same? Since it has very low resistance |
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| 44619. |
Example of electrolytic decomposition |
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Answer» Acidified hydogen oxide ------ electrolytic refining....------. H2 +o2 2AGBR_______2ag +BR2 2H2O -------> 2H2 + O2..... arrow ke upar electricity likh dena...... 2H2O---------elec.-----------2H2+O2 |
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| 44620. |
The depletion of ozone layer is a cause of concern.why. |
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Answer» The ozone layer present in our atmosphere protects us from the harmful Ultra Violet rays of the sun which can cause skin cancer and other diseases. This ozone prevents the UV rays from reaching earth. so the depletion of ozone layer is a matter of concern for everyone. Becoz the ozone layer is securing our earth from harmful rays of the sun. if the harmful rays of sun will come to earth then the human being\'s body will be destroyed.. the planet earth will be destroyed................. |
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| 44621. |
What is the importance of DNA copying in the reproduction . |
| Answer» DNA copying is important for reproduction. Additional copies of DNA are made during replication; which is necessary for the new cells formed after cell division. Moreover, some minor alterations during DNA replication are responsible for bringing variations in the long run. | |
| 44622. |
Actic acld |
| Answer» | |
| 44623. |
What is silviculture. |
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Answer» Silviculture is the practice of controlling the growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin silvi- + culture. The study of forests and woods is termed silvology. Rearing of silk |
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| 44624. |
One more question. Guys .... Discuss the case in which convex lens act as diverging lens?? |
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Answer» When it is placed inside liquid of refractive index greater than that of material of lens...then it behaves s diverging lens When it is placed inside a liquid of refractive index greater than that of the material of the lens, it behaves like a diverging lens........ |
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| 44625. |
what is emergent ray? |
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Answer» Emergent ray is the ray which emerges at the source of light.incident ray is an acronym of emergent ray.it is a light which leaves a mediumThe light rays which are emitted by the source of light be it a bulb or a natural source like sun or any other device such as a laser. The refracted ray which is emerged out of a medium after refraction is emergent ray |
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| 44626. |
5no me choices kitni ata hai |
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Answer» Pkka 3 one from each sub. Syd 2,3 3 |
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| 44627. |
Draw structure of third member of alcohol series???? Plz do answer if someone knows... |
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Answer» Ya, ok tq so much.. Genral formula of alcohol is CnH2n+1oH hai satisfy krke dekho C3 H7 OH |
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| 44628. |
What is universal indicator? Give its uses. |
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Answer» Universal indicator to phenolphthalein hai ur synthetic bhi Universal indicator is a mixture of many different indicator which gives different colour at different ph values of entire ph scale Litmus and pH paper examples of universal indicators it is used to tell if a solution is acidic or basic |
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| 44629. |
What is indicators? Give two examples of natural and artificial indicators. |
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Answer» Natural indicators are litmus and turmeric Indicator is a material which is used to find that weather a substance is acidic or basic. Natural : turmeric and litmusArtificial :phenolpthalein and methyl orange |
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| 44630. |
What are the factor affecting rate of reaction ? |
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Answer» Temperature and reactivity of elements Temprature and to boost reaction u should use catalyst |
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| 44631. |
Difference between monohybrid and dihybrid |
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Answer» Monohybrid-one pair of contrasting character.Dihybrid-two pair of contrasting character. In monohybrid one contrasting characteristics of an organism is crossed whereas in dihybrid two contrasting characteristics are crossed. |
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| 44632. |
,what are water said managnment. |
| Answer» Scientific soil and water conservation in oder to increase biomass production thanks | |
| 44633. |
What are autotrophs and heterotrophs give an example with the definition? |
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Answer» Autotrophic are those who are self dependent and make their own food by the process of photosynthesis. Ex plantHeterotrophic are those are depend on others for their food Ex humanbeing Autotrophs - those who can make their own food by the process of photosynthesis.are known as autotrophs.for ex green plants.Heterotrophs-those organisms who depend on other organism for their food is known as heterotrophs.for ex human beings. |
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| 44634. |
How does our body respond when adranaline gland secreted hormon. |
| Answer» It provide oxygen | |
| 44635. |
Why balance equations |
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Answer» We have studied in class 9 law of conservation of mass it is based on these ......okay To make same no.of atom on both side of equation What? Balancing equations is used because of law of conservation of mass According to law of conservation of mass Mtlb |
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| 44636. |
It is neutralisation reactionTry to understand |
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Answer» Sustainable development means development without damaging the environment is knows as sustainable development. Ex -solar plant The reaction in which acid and base react to form salt is knows as neutrilsation reaction. Example Nacl what is sustainable management ressorce |
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| 44637. |
What is lanthanoid contraction?? |
| Answer» Out of syllabus | |
| 44638. |
But no one see they are ions |
| Answer» What ions | |
| 44639. |
Why does menstruation occur...... |
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Answer» After a month it was happened when an fertilised egg can\'t get germ cell or gaemetes then the egg burst or mensturation was start when the egg in not fertilesd the eggs with blood If post fertilisation does not occurs then the ovum along with sperm near mucus gets flushed out along with blood When egg does not get sperm |
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| 44640. |
What is exothermic and endothermic reaction ? Is saponification exothermic or endothermic reaction |
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Answer» This answer may help you. Exothermic reaction:-the reaction in which heat comes out is called exothermic reaction. Example-respiration Endothermic reaction :-the reaction in which heat is abosured is called endothermic reaction. Ex-photosynthesis Sponfication reaction is endothermic reaction --->Exothermic reaction is a reaction in which heat is evolved ---->Endothermic reaction is a reaction in which heat is used for the happening of reaction>>>>Sponification reaction is a endothermic reaction See ncert it is difficult in typing |
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| 44641. |
what are ionic compound? list two properties of these compound |
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Answer» They are soluble in water 2nd property is they hav high melting and boiling poi t 1st property they are crystalline solids Compounds formed by transfer of electrons |
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| 44642. |
What is spore formation. |
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Answer» Such as rhizopus, bacteria etc Spore formation is part of asexual reproduction which is found non flowering plants such as .In this asexual reproduction the parent produce hundred of tiny which can grow into new plant. Spores are present on sprogania bulb like structure covered with thick walls protects them until they get comfortable environment |
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| 44643. |
Why a milkman adds a very small amount of baking soda in a fresh milk? |
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Answer» Fresh milk is slightly acidic naturally. Fresh milk is made slightly alkaline by adding a little amount of baking soda so that it may not sour easily due to formation of lactic acid. Nhi karega toh lactic acid form karega aur agar extra form ho gya toh milk kharab ho jayega , isliye to prevent this they add a little amou t of baking soda which neutralises the acid and keeps the milk ...... Prevent the formation of lactic acid Taki latic acid ka formation naa ho |
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| 44644. |
What i food chain |
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Answer» The sequence of livings in which one organism consume other orgnism to transfer of energy is known by food chain, for Ex-? -? -? -?-? -?. The series of organism take part at various biotic levels to form a food chain. Each step of the food chain forms a tropic level. The producers (green plants) are at the first tropic level. ... An average of 10% of food is turned into its own body which is again consumed by the secondary consumers. The series of organism in which one organism eats another organism as food is known as a food chain. |
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| 44645. |
Mirror pr image kitni speed se bnti hai? |
| Answer» Light ke speed se hi | |
| 44646. |
describe in brief the cleans of soap .why do soap not form ladder in hard water |
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Answer» Soaps are sodium or potassium salts of long chain of carboxylic acids. most dirt is oily in nature, soap molecule form structure called micelles were one end of the molecule is towards dirt, the ionic end face outside this forms an emension in water which helps in pulling out dirt from fabric and the soap micelle helps in dissolving the dirt in water. The presence of calsium or magnesium ions in the water form hard water and thats why soap do not form lather in hard water. Soap is a sodium and potassium salt of long chain fatty acid or carboxylic acid. When soap is used for cleansing action it will form micelles around the dirt partical and grease. The hydrophobic part(which hates water) of micelle attach around the gease(away from the water) and the hydrophilic part(which loves water) is towards water. Then after agitation these dirt and micelle will detached from the cloth and the cloth is clean. The soap reacts with the calcium and magnesium ions which are present in the hard water and produces a insoluble substance called "scum".That\'s why soap doesnot react with hard water. Because of presence of calcium or magnesium ions |
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| 44647. |
What is plant harmones |
| Answer» Chemical substances which contol and coordinate the plants | |
| 44648. |
Write the out line of N2 cycle |
| Answer» 9th ki book uthake dekh | |
| 44649. |
What is the use of a) ammature b) split ring c) brushes in electric motor and generator |
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Answer» There are two carbon brushes B1and B2 made up of graphite because graphite is a good conductor of electricity .brush B1 is connected to(+) terminal of battery and brush B2 conected to(-)terminal of bettery.. They helps in continuous flow of current...... B) changes the direction of current split ring ....there are two solit rings R1and R2 split rings R1is connected to the point P of armature coil while right R2 is connected to the S point of coil. it help to rotate the armature coil.... Not b its ans of c b) make contact with rotating rings of commutator and through them to supply current to the coil Armature coil... There is a long straight wire loop PQRS made up of coopr wire we use only a single wire loop . This is knows as armature coil.... |
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| 44650. |
Chapter 5 question |
| Answer» What? | |