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InterviewSolution
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.
| 501. |
Draw the neat diagram of froth floatation process for the concentration for sulphide ore why we add pine oil to the mixture in this process? |
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Answer» Solution :1) The mineral particles in the ore are preferentially wetted by the OIL and flot on the top of the froath. 2) The gangue particles are wetted by WATER and settle down. 3) THUS, the minerals can be separated from the gangue by adding pine oil. 
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| 502. |
One horse power is equal to : (a) 1000W (b) 500W (c) 764W (d) 746W |
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Answer» 1000 W |
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| 503. |
A hunter has a maching gun that can fire 50g bullets with a velocity of 150"ms"^(-1). A 60 kg tiger springs at him with a velocity of 10"ms"^(-1). How many bullets must the hunter fire into the target so as to stop him in his track ? |
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Answer» SOLUTION :Given m =MASS of bullet = 50 gm = 0.50 kg M = mass of tiger = 60 kg v= Velocity of bullet = 100 m/s V = Velocity of tiger =-10m/s (∴ It is coming from opposite direction n =no. of BULLETS fired PER second at the tiger so as to stop it.) `P_i =0,` before firing ...(i) `P_f= n(mv) + MV ...(ii)` From the law of conservation of MOMENTUM `rArr 0=n(mv)+MV` `rArr n=MV)/(mv)` `=(-60 xx (-10))/(0.05 xx 100)=120` |
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| 504. |
The phenomenon of electromagneticinduction is……. |
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Answer» the PROCESS of charging a body |
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| 505. |
Why are the methods of conserving water resources? |
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Answer» Solution :Conservation of water resources For conservation and management of fresh water following methods can be employed : 1. Reducing agricultural water wastage by increasing efficiency of irrigation system. 2. AFFORESTATION and protection of watersheds to improve ECONOMY. 3. Formation of artifical clouds, so that a change can be brought in the atmosphere. 4. Changes in the VEGETATION of a particular area, so that even in the dry season maximum AMOUNT of water can be stored. In addition to this dams should be constructed to stop the drainage of rain water. 5. Control the distribution of water by constructing big dams. 6. Desalinization of sea water and saline ground water. 7. Proper utilization of underground water. 9. Melt the glaciers and snow for using as a fresh water resource. 10. Regular dredging and desiltation of water bodies. |
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| 506. |
Give the application of torque . |
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Answer» Solution :(i) Gears : A gear is a circularwheel with teeth around its RIM . It helps to change the speed of rotation of a wheel by changingthe torque and helpsto transmit power . (ii) Seasaw : Whenthe heavierperson comescloserto the pivot point ( fulcrum ) the distanceof the line of ACTION of the forcedecreases . It causes less amount of torque to ACT on it . This enablesthe lighterperson to lift the heavierperson . (III) SteeringWheel : A small steering wheel enablesyou to manoeuorea car easily by transferringa torqueto the wheels with lesseffort . |
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| 507. |
The only correct statement for the following electric circuit is : |
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Answer» The voltmeter has been CORRECTLY CONNECTED in the circuit |
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| 508. |
How do government schemes help to the distress children ? |
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Answer» Solution :i. GOVERNMENT PUBLISHES phone numbers/helping numbers to help children in dustress or facing any type of issues. II. Children in DISTRESS contact the HELPLINE and narrate their issues. iii. Government offers needed help and guidelines to such children. |
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| 509. |
State the two conditions under which a force does no work? |
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Answer» Solution :(i) DISPLACEMENT is ZERO or it is PERPENDICULAR to force. (ii) Conservative force moves a body over a closed PATH. |
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| 510. |
Keeping the temperature as constant, a gas is compressed four times of its initial pressure. The volume of gas in the container changing from 20cc (V_(1)" cc") to V_(2) cc. find the final volume V_(2). |
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Answer» <P> Solution :Initial pressure `(P_(1))=P`FINA pressure `(P_(2))=4P` Initial volume`(V_(1))=2ee =320 cm^(2)` Final volume `(V_(2))=?` Using Boyle.s Law,PV= constant `P_(1)V_(1)=P_(2)V_(2)` `V_(2)=(P_(1))/(P_(2))xxV_(1)=(P)/(4P)xx20 cm^(3)` `V_(2)=5 cm^(3)` |
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| 512. |
230 joules were spent inlifting a 10kg wieight to a height of 2m. Calculate the acceleration with which it was raised Take g=10ms^(2). |
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Answer» SOLUTION :`W=mgh+mah=m(g+a)H` `:.a=1.5m//s^(2)` |
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| 513. |
In a circuit, a voltmeter is always connected ......... to the electrical component. |
| Answer» SOLUTION :in PARALLEL | |
| 514. |
How many light years are there in 1 metre? |
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Answer» `1.057xx10^(-16)LY` |
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| 515. |
Two bodies with kinetic energies in the ratio 4:1 are moving with equal linear momentum. The ratio of their masses is |
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Answer» SOLUTION :`E ALPHA 1/m` or `m alpha 1/E` `(m_(1))/(m_(2))=(E_(2))/(E_(1))=1/4` |
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| 516. |
Mention the transformation of energy that takes place in a thermal power plant. Briefly. |
| Answer» SOLUTION :Large amount of fossil fuels are BURNT EVERYDAY in power stations to heat up water to produce steam which further runs the turbine to generate electricity. Many thermal plants are set up near coal or OIL fields. In these plants fuel is burnt to produce heat ENERGY which is converted into electrical energy. | |
| 517. |
According to Ohm's Law many types of materials are there ? |
| Answer» SOLUTION :TWO (OHMIC and NON - ohmic). | |
| 518. |
On which effect of electriccurrentdoes the fuse work ? |
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Answer» MAGNETICEFFECT of ELECTRICCURRENT |
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| 519. |
Althought coal and petroleum are produced by degradation of biomass , yet we need conserve them . Why ? |
| Answer» Solution :Both the energy SOURCES , coal and PETROLEUM , take MILLIONS of years for their formation . As these resources are being utilised at a much FASTER rate than their formation , they will be exhausted in the near future . Hence , they need to be conserved. | |
| 520. |
The refractive index of glass is 1*5 from a point P inside a glass slab, draw rays PQ, PB and PC incident on the glass-air surface at an angle of incidence 30^(@),42^(@) and 60^(@) respectively. (a) In the diagram show the approximate direction of these rays as they emerge out of the slab. (b) What is the angle of refraction for the ray PB (Take sin42^(@)=(2)/(3)) |
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| 521. |
State and prove the law of conservation of linear momentum . |
Answer» Solution :Law statesthat " There is no changein the LINEARMOMENTUM of a system of bodies as long as no net external force acts on them "  Proof: Lettwo bodies A and B havingmasses `m_1` and `m_2` MOVE with initial velocity `u_1 and u_2` in a straight LINE . LET the velocity of the firstbody be higherthan that of the second body . i.e., `u_1 gt u_2` . Duringan interval of time t second , they tendto havea collision . Afterthe impact, both of them move along the same straightline with a velocity `v_1 and v_2` respectively . Forceon body B due to A , `F_B=m_1(v_1-u_1)//t` Forceon body A due to B , `F_A=m_2(v_2-u_2)//t` By Newton's III lawof motion , Action force = Reaction force `F_A=-F_B` `(m_2(v_2-u_2))/(cancel(t))= (-m_1(v_2-u_2))/(cancel(t))` `m_1v_1=m_2v_2=m_1u_1+m_2u_2`-------------(A) The aboveequation confirmsin the absenceof an external force , the algebraic sum of the momenutm after collison is numerically equal to the algebraic sum of the MOMENTUM before collision . Hence the law ofconservation of linearmomentum is proved. |
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| 522. |
What provides the centripetal force to a car taking a turn on a level road ? |
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| 523. |
The magnetic field lines associated with current carrying straight conductor is in anti clockwise direction. If the conductor was held horizontally along east-west direction, what is the direction of current through it ? Explain it with the help of diagram. Name and state the rule applied to determine the direction of magnetic field. Ifthe conductor is held vertically and currentflows from north to south, what will be the direction of magnetic field lines. Draw diagram. |
Answer» Solution :Direction of current will be from East to West direction. Maxwell.s right hand THUMB RULE  STATEMENT : Imagine that you are holding the current CARRYING wire in your right hand so that your thumb points in the direction of current, then the direction of your fingers encircle the wire will give the direction of magnetic field. 
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| 524. |
Which of the following property of a proton can change while it moves freely in a magnetic field ? (There may be more than one correct answer.) |
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Answer» Mass |
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| 525. |
You are given a galvanometer, an electroplating equipment, a key and two sources of electricity. Give two different experimental set ups to find whether any of the given sources is AC or DC source. |
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Answer» Solution :(a) We can connect the galvanometer to any ONE of the sources using a key in the circuit. If the galvanometer shows definite deflection in a given DIRECTION, the source taken is d.c. source. If the given source is a.c. source, the average deflection shown by the galvanometer will be ZERO. (b) We can also connect the electroplating equipment to any one of the source using a key in the circuit. If electroplating takes place, the source USED is d.c. source. In case of AC source, since the direction of current changes in direction PERIODICALLY and alternatively, there is no definite shifting of the ions of the electrolyte and hence no electroplating takes place. |
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| 526. |
A ball of mass 10 g falls from a height of y 5 m. It rebounds from the ground to a height of4m. Find : (a) the initial potential energy of the ball,(b) the kinetic energy of the ball just before the ground. striking the ground, (c) the kinetic energy of the ball after strikingthe ground ,and (d) the loss in kinetic energy on striking the ground .Take g=9.8 m s^(-2). |
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Answer» Solution :Gicen m=10 g=`(10)/(1000) kg `=0.01 kg h=5 m,g=9.8 m `s^(-2)` .h. =4 m. (a) Initial potential energy of the ball =mgh `0.01xx9.8xx5=0.49 J` (b)Kinetic energy of the ball just before striking the ground =Iniial potential energy of the ball =0.49 J. (c)Kinetic energy of the ball after striking the ground =Potential energy of ball at the highest POINT after REBOUND. =mgh.=`0.01xx9.8xx4=0.392J` (d) Loss in kinetic energy on striking the ground =Initial kinetic energy -FINAL kinetic energy =0.49 J-0.392 J=0.098 J NOTE:This energy APPEARS in the form of heat energy and sound energy when the ball strikes the ground . |
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| 527. |
Among the following statements. 1. A discharge lamp uses a discharge tube which is filled with a gas at a very low pressure. 2. Always white light is emitted independent of gas taken in the lamp. |
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Answer» Only 1 is true |
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| 528. |
In thermal power plants, the turbines work on solar energy. Is the above statement correct?Justify your answer |
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| 529. |
Explain the Excretory System of Leech briefly. |
| Answer» Solution :In LEECH, excretion takes place by segmentally arranged paired TUBULES called NEPHRIDIA. There are 17 pairs of nephridia which opens out by nephridiopores from `6^(th)` to `22^(nd)`segments. | |
| 530. |
Measure of two quantities along with the precision of respective measuring instrument is A=2.5ms^(-1)+-0.5ms^(-1), B=0.10s +- 0.01 s. The value of AB will be |
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Answer» `(0.25+-0.08)m` |
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| 531. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of population.List two common signs of sexual maturation in boys and girls. |
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Answer» Solution :(i) Appearance of pubic hair. (ii) Skin BECOMES OILY and MAY BREAK into pimples. |
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| 532. |
motorboat is racing towards north at 25 kmh^(-1) and the water current in that region is 10 kmh^(-1) in the direction of 60° east of south. Find the resultant velocity of the boat. |
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Answer» SOLUTION :`V=21.8 KMH^(-1)` ANGLE with NORTH, `theta=23.4` |
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| 533. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of population.What is the result of reckless female foeticide ? |
| Answer» Solution :Selective Medical Termination of Pregnancy (MTP) of female foetus USING amniocentesis is the MAIN reason behind decline female-male sex RATIO in our country. This is because many sections of our SOCIETY considered girl CHILD as a burden. | |
| 534. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of population.Which contraceptive method changes the hormonal balance of the body ? |
| Answer» Solution :ORAL Contraceptive Pills (OCPs) CHANGE the HORMONAL BALANCE of the body. | |
| 535. |
A body is thrown up with an initial velocity u and covers a maximum hieght of h, then h isequal to |
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Answer» `(u^(2))/(2g)` |
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| 536. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of population.Write two factors that determine the size of a population. |
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Answer» SOLUTION :TWO factors that determine size of a population : (i) Birth RATE (II) Death rate |
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| 537. |
Few years back, disposable plastic cups were used for serving tea in trains. The impact caused by the disposal of millions of these cups on a daily basis caused a serious environment concern and disposable Kulhads, made of clay, were used instead. However, this resulted in loss of the fertile top-soil and hence was discontinued and has now been replaced by disposable paper cups. Answer the following questions based on above information: (i) What is the advantage of using disposable paper-cups over disposable plastic cup? (ii) Which values are promoted by using' disposable' and 'paper cups'. (iii) Can such practices be followed at domestic level also? Give reasons. |
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Answer» Solution :(i) PAPER cups are biodegradable whereas plastic is non-biodegradable and hence they LATTER is more environmental friendly. (ii) Environmental care, recycling of natural RESOURCES, hygiene. (iii) Better hygienic care practices can be followed at home and hence same utensils/MATERIALS can be used again and again resulting in judicious use of materials. |
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| 538. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.Human body is made up of five important components, of which water is the main component. Food as well as potable water are essential for every human being. The food is obtained from plants through agriculture. Pesticides are being used extensively for a high yield in the fields. These pesticides are absorbed by the plants from the soil along with water and minerals and from the water bodies these pesticides are taken up by the aquatic animals and plants. As these chemicals are not biodegradable, they get accumulated progressively at each trophic level. The maximum concentration of these chemicals gets accumulated in our bodies and greatly affects the health of our mind and body.Why is the maximum concentration of pesticides found in human beings ? |
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Answer» Solution :The PHENOMENON of progressive INCREASE in concentration of certain harmful non-biodegradable chemicals such as DDT at different levels of food CHAIN is CALLED biological magnification or biomagnifications. The concentration of harmful chemicals will be different at different trophic levels. It will be LOWEST in the first trophic level and highest in the last trophic level of the food chain. |
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| 539. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.Human body is made up of five important components, of which water is the main component. Food as well as potable water are essential for every human being. The food is obtained from plants through agriculture. Pesticides are being used extensively for a high yield in the fields. These pesticides are absorbed by the plants from the soil along with water and minerals and from the water bodies these pesticides are taken up by the aquatic animals and plants. As these chemicals are not biodegradable, they get accumulated progressively at each trophic level. The maximum concentration of these chemicals gets accumulated in our bodies and greatly affects the health of our mind and body.Give one method which could be applied to reduce our intake of pesticides through food to some extent. |
| Answer» SOLUTION :If we practise organic farming, which does not INVOLVE USE of chemicals then our intake of pesticides through FOOD will reduce. | |
| 540. |
Which of the following will produce lesser pollution problems? |
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Answer» NUCLEAR fission |
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| 541. |
(i) The refractive index of diamond is 2.42. What is the meaning of this statement ? (ii) Name a liquid whose mass density is less than of water but it is optically denser than water. |
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Answer» SOLUTION :(i) N/A (II) Kerosene oil is a liquid whose mass DENSITY is less than that of water (i.e., kerosene oil is lighter than water) but it is OPTICALLY denser than water (i.e., refractive index of kerosene oil is more than that of water.) |
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| 542. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.Human body is made up of five important components, of which water is the main component. Food as well as potable water are essential for every human being. The food is obtained from plants through agriculture. Pesticides are being used extensively for a high yield in the fields. These pesticides are absorbed by the plants from the soil along with water and minerals and from the water bodies these pesticides are taken up by the aquatic animals and plants. As these chemicals are not biodegradable, they get accumulated progressively at each trophic level. The maximum concentration of these chemicals gets accumulated in our bodies and greatly affects the health of our mind and body.Various steps in a food chain represent : |
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Answer» FOOD web |
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| 543. |
A convex lens forms a real and inverted image of aneedle at a distance of 50cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object ? Also, find the power of the lens. |
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Answer» Solution :Since the image is real and same SIZE. The position of image should be at 2F It is given that the image of the NEEDLE is formed at a distance of 50 cm from the convex lens. Hence, the needle is PLACED in front of the lens at a distance of 50 cm. Object distance, U = - 50 cm Image distance, V = 50 cm |
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| 544. |
What will you do if, your friend has developed the hobby of snapping selfies ? Why? |
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Answer» Solution :The bad habit of constantly TAKING selfies may endanger the life of a person as he is unaware of the RISKS in his surroundings. If I find the my friend has DEVELOPED they HOBBY of snapping selfies: i. I will warn him to be cereful while clicking selfies and to be aware about the surrounding so as to avoid accidents. ii. I will try to persuade him to avoid clicking selfies at every occasion and to RATHER enjoy the moment with friends and/or family. |
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| 545. |
Answer question numbers (a) to (d) on the basis of your understanding of the following paragraph and the related studied concepts.Human body is made up of five important components, of which water is the main component. Food as well as potable water are essential for every human being. The food is obtained from plants through agriculture. Pesticides are being used extensively for a high yield in the fields. These pesticides are absorbed by the plants from the soil along with water and minerals and from the water bodies these pesticides are taken up by the aquatic animals and plants. As these chemicals are not biodegradable, they get accumulated progressively at each trophic level. The maximum concentration of these chemicals gets accumulated in our bodies and greatly affects the health of our mind and body.With regard to various food chains operating in an ecosystem, man is a : |
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Answer» CONSUMER |
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| 546. |
State the essential condition for the addition of vectors. |
| Answer» SOLUTION :They must REPRESENT the physical quantities of same NATURE. | |
| 547. |
Draw a neat diagram of a biogas plant and label (i) inlet of slurry, (ii) digester and (iii) gas outlet. |
Answer» SOLUTION :
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| 548. |
Asserion: In parallel combination of electrical appliances, the total power consumption is equal to the sum of powers of the individual appliances. Reason: Charges move from higher potential to lower potential. |
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Answer» if both the ASSERTION and the REASON are trueand the reason is the CORRECT explanation of the assertion. |
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| 549. |
Where is the centre of gravity of a uniform ring situated ? |
| Answer» SOLUTION :At the CENTRE of RING. | |
| 550. |
How can you say that an individual can contribute or make a difference to the management of (i) Forests and wildlife, (ii)Water resources , and (iii)Coal and petroleum ? |
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Answer» Solution :(i)Forests and wildlife : (a)I will stress on the conservation of biodiversity (b)I will prevent cutting down of trees in forest , this will itself protect the HABITAT of wild animals. (c )I will try to EDUCATE people on the importance of forests andtheir role in our life. (ii)Water resources : (a)I will stress on the conservation of water byturning off the TAP while brushing or shaving. (b)I will use potable water for drinking purpose only andnot for cleaning car , or giving water to plant. (c )The judicious use of water is essential to to avoid undue WASTAGE of water. (d)I will adopt rainwater harvesting system. (iii)Coal and Petroleum :These are the main sources of energy today . We can save them in many ways . for example (a) Using fluorescent tubes instead of lamps using fossil fuels. (b)Using solar devices instead of fuels. (c)Prefer walking or CYCLING rather than using vehicles or public transport to save petrol. (d)I will getmy car properly tuned to imporove fuel effciency. |
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