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This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
In figure, a ray of light PQ is incident normally on the face AB of an equilateral glass prism. Complete the ray diagram showing its emergence into air after passing through the prism. Take critical angle for glass=42^(@). (a) Write the angles of incidence at the faces AB and AC of the prism. (b) Name the phenomenon which the ray of light suffers at the face AB, AC and BC of the prism. |
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Answer» (b) At the face AB-refraction, at the face AC-total internal REFLECTION, at the face BC-refraction. |
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| 2. |
In which way is science of heredity useful these days ? |
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Answer» SOLUTION :The science of heredity is useful in the following ways : (1) For diagnosis of hereditary disorders. (2) For TREATMENT of hereditary disorders (3) For prevention of hereditary disorders (4) For production of hybrid VARIETIES of animals and plants (5) For using microbes in the INDUSTRIAL processes. |
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| 3. |
(a) write the name and molecular formula of an organic compound having its name suffixed with -ol and having two carbon atoms in the molecule. With the help of a balanced chemical equation indicate what happens when it is heated with excess of conc. H_(2)SO_(4) ? (b) What is substitution reaction ? Give an example |
| Answer» Solution :`H-overset(H)overset(|)underset(H)underset(|)-overset(H)overset(|)underset(OH)underset(|)-H rArr C_(2)H_(6)O, CH_(3)-CH_(2)OH overset(Delta)underset({:(H_(2)SO),((-H_(2)O)):})tounderset("Ethene")(CH_2=CH_2)` | |
| 4. |
The wheels of vehicles are provided with mudguards. Why ? |
| Answer» Solution :When the wheel rotates at a high speed, the MUD STICKING to the wheel flies off tangentially, this is due to INERTIA of direction. If order that the flying mud does not SPIRAL the clothes of PASSER by the wheels are provided with mudguards . | |
| 5. |
There is increasing competition to upload the videos of road accidents instead of helping the victims. What is the mentaality of such people ? |
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Answer» Solution :a. People taking videos at the site of acidents are irresponsible, insensitive and lack helpful nature. b. They are more concerned about their POSTS on WhatsApp and Facebook and about getting more likes and comments. c. Also, there is possiblility of these people being under stress and that they PERFORM such activities to relieve their stress. d. Such activities are decleared as MENTAL illness by medical science and hence people indulging in such activities MIGHT be mentally sick. |
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| 6. |
The amount of water vapour in air is determined in terms of its .............. . |
| Answer» SOLUTION :HUMIDITY | |
| 7. |
Plastic production is increasing day by day in spite of the fact that plastic is harmful for the environment. Based on the above statement answer the following. (i) What are the harmful effects of plastic usage? (ii) In our day to day situation what are the alternatives that we can use instead of plastics. |
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Answer» SOLUTION :(i) (a) Environmental pollution. (b) Burning PLASTICS can cause pollution. (c) PLASTIC cause harm to the cattle/animals if enter inside their alimentary CANAL. (ii) Paper bags/ jute bags can be used instead of plastic bags. |
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| 8. |
Which of the following circuit symbols is usedto represent an electric cell? |
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| 9. |
Which physical quantity is conserved when a planet revolves around the sun ? |
| Answer» SOLUTION :ANGULAR MOMENTUM of PLANET. | |
| 10. |
Derive an expression for heat produced in a conductor using Joule's law of heating. |
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Answer» <P> Solution :Let 'V' be the potential difference applied across the two terminals of a resistor of resistance 'R' by a cell and 'I' be the current flowing through the resistor in time 't'.ii. If charge Q flows through the resistor, then the electrical power 'P' is given by `P=("Energy")/("time")"...(1)"` where, energy is the work done by cell to move charge Q across the resistor `therefore"Energy " = VxxQ"...(2)"` `therefore"P"=(VQ)/(t)"....[from equations (1) and (2)]"` `=VI"..."(because(Q)/(t)=I)"....(3)"` iii. The cell PROVIDES the energy to the resistor which is CONVERTED into heat energy, given by `H=Pxxt=VxxIxxt"...[from (3)](4)"` iv. According to Ohm's LAW, `V=IR"...(5)"` From EQUATION (4) and (5), `H=(V^(2)t)/(R) or H=I^(2)Rt` This is called as Joule's law of heating. |
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| 11. |
Where does refraction of light rays occur in the human eye ? |
| Answer» SOLUTION :Outer SURFACE of the CORNEA and eye lens. | |
| 12. |
(a) Name the organs that form the excretory system in human beings.(b) Describe in brief how urine is produced in human body. |
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Answer» Solution :(a) Excretory system in man includes a pair of kidneys, ureters, a urinary bladder and a urethra. (B) PROCESS of urine formation : (i) Ultrafiltration : When the renal artery, carrying impure blood BREAKS into capillaries in the Bowman.s capsule, it increases pressure in the blood which results in formation of nephric filtrate composed of mainly water and ions, GLUCOSE, amino acid, urea, hormones, etc. All these remain dissolved in water. (ii) SELECTIVE Reabsorption : Most (90%) of the water and dissolved materials essential for the body are reabsorbed, back into the blood for e.g., amino acids, glucose, water, `Na^(+), CI^(-), K^(+)` etc. (iii) Secretion : Certain cells near the distal end secrete bicarbonate ions and complete the composition of urine. |
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| 13. |
Assertion (A) : The end of a solenoid where currentapperarsto flow clockwise behaves as a magnetic south pole . Reason (R) : Direction of magnetic fieldassociated witha currentcarryingconductor /coil is foundby applyingis found by applying right hand thumb rule. |
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Answer» Both (A) and (R) are TRUE and (R) is CORRECT explanation of the ASSERTION |
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| 14. |
The focal length of a concave lens is 30 cm. At what distance should the object be placed from the lens so that it forms an image at 20cm from the lens? |
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Answer» SOLUTION :`(1)/(v)-(1)/(u)=(1)/(f) " OR " (1)/(u)=(1)/(v)-(1)/(f)` `(1)/(u)= (1)/(-20)- (1)/((-30))=(1)/(20)+(1)/(30)` `(1)/(u)= (-3+2)/(60) ""(1)/(u)=(1)/(60) or u = -60cm` |
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| 15. |
Whilecoolinghotwaterin naturalambience, itfollows______ Typeofbehaviorout ofthe following. |
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| 16. |
Older mothershave greater chanceof conceiving abnormal children. |
| Answer» SOLUTION :(1) In older women the menopausal age approaches. (2)The oocytes, released from ovaries during this PHASE are not normal. (3) Their meiotic cell division is abnormal ANDTHUS oocyte BECOMES abnormal too. (4) If such abnormal oocytes are fertilized, the baby is born with many genetic PROBLEMS. e.g. Down's syndrome or Turner's syndrome. | |
| 17. |
The kinetic energy is water stored in dam is converted into potential energy of water in a hydropower plant. Do you agree? Why? Why not?. |
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Answer» |
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| 18. |
(i) Two circular coils P and Q are kept close to each other, of which coil P carries a current. If coil P is moved towards Q, will some current be induced in coil Q? Give reason for your answer and name the phenomenon involved. (ii) What happens if coil P is moved away from Q? (iii) State any two methods of inducing current in a coil. |
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Answer» Solution :(i) When coil P is moved TOWARDS Q, current will be induced in coil Q. This is because on moving P the magnetic field associated with Q increasesand so a current is induced. The phenomenon is ELECTROMAGNETIC induction. (ii) If P is moved away from Q, the field associated with Q will decrease and a current will be induced but in the opposite direction. (III) Current can be induced in a coil by (a) moving a magnet towards or away from the coil (b) moving a coil towards or away from a magnet(C ) rotating a coil within a magnetic field. |
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| 19. |
What is piracy? |
| Answer» Solution :Piracy means misuse or ILLEGAL SALE of the somebody ELSE's written literature, software,photos , videos,music,etc, which is OBTAINED from the INTERNET. | |
| 20. |
When a person is said to have developed cataract? How is the vision of such a person restored? |
| Answer» Solution :When the crystalline lens of eye becomes HAZY (or ever OPAQUE) due to the formation of thin membrane over it, this CAUSES partial or complete loss of vision. This defect of eye is called cataract. The vision of the defected eye can be RESTORED by the cataract surgery. | |
| 21. |
Assertion (A) : A commercial motor uses a soft iron core on whichthe coil carrying currentin wound. Reason (R) : Presence of soft iron core enhances the powerof the motor as it increase the magnetic field . |
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Answer» Both (A) and (R) are TRUE and (R) is correct explanation of the ASSERTION |
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| 22. |
Name the physical quantity that determines the rate at which energy is delivered by an electric cunent. State and define the unit of this physical quantity. |
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Answer» Solution :Quantity : Electric power UNIT : Watt 1 Watt is the power CONSUMED by a DEVICE that carries 1 A of current when OPERATED at a potential DIFFERENCE of 1 V. |
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| 23. |
soundtravelsfastestin |
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Answer» water |
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| 24. |
Explain briefly the following day to day events: (a) A swimming pool appears shallower than what it actually is. (b) A convex lens can be used as a magnifier, but a concave lens cannot be. ( c) A convex mirror is used as a rear view mirror by the drivers of motor vehicles. (d) A concave mirror is used by ENT specialists. (e) A convex mirror is used as a refleactor in street lamps. |
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Answer» Solution :(a) It happens on account of refraction of light. The rays starting from the bottom of the tank bend away from normal at the surface of water. That is why bottom of the tank appears RAISED. (b) When an object is held between optical centreand principal focus of a convex lens, it forms a virtual, erect and magnified image. That is why a convex lens acts as a magnifier. But for any position of the object, image formed by a concave lens is virtual, erect and shorter. Therefore, a concave lens cannot act as magnifier. (c ) This is because image formed by a convex mirror is ALWAYS virtual, erect and smaller in size. The mirror has a large field of VIEW. (d) This is because a concave mirror can concentrate a PARALLEL beam of light onto a particular part of the body to be examined. (e) A convex mirror is used as a reflector in street lamps because it would diverge the rays of light FALLING on it from the source. |
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| 25. |
Impulseis equal to _______ |
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Answer» RATE of CHANGE of momentum |
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| 26. |
Principal focus of a ________________ mirror is a real point but for a _______________ mirror it is a virtual point. |
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Answer» |
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| 27. |
a) What are groups and period in the periodic table? b) Two elements M and N belong to group I and II respectively and are in the same period of the periodic table. How do the following properties of M and N vary?1) Sizes of their atoms 2) Their metallic characters. 3) Their valencies informing oxides. 4) Molecular formula of their chlorides. |
| Answer» Solution : a) The vertical COLUMNS in the periodic table are called group. The horizontal rows in the periodic table are called periods. b) 1. M and N belong to the same PERIOD but I and II. Therefore N will be smaller than Mas atomic size is decreasing from left to right. 2. M is more metallic than N. Metallic character goes on decreasing from left to right as tendency to lose electrons decreases DUE to decrease in atomic size. 3. Their valencies are 1 and 2 respectively in forming oxides. Valency goes on increasing first and then INCREASES. 4. `MCI, NCI_2`are molecular FORMULAE of their chlorides. | |
| 28. |
Which of the following is the cause of mental stress ? |
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Answer» MEDITATION |
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| 29. |
A fish is looking at a 1*0m high plant at the edge of a pond. Will the plant appear to the fish shorter or taller than its actual height ? Draw a ray diagram to support your answer. |
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| 30. |
What do we call the degenerated or partially developed useless organs in living organisms? Enlist such organs in human body. How are the same organs useful in other animals? |
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Answer» Solution :(1) Vestigial ORGANS are degenerated or underdeveloped organs of organisms which do not perform any function. (2) According to the principle of NATURAL selection, such organs are on the verge of DISAPPEARANCE. But it takes many millions of years for its complete vanishing. (3) The vestigial organs in one animal may be of use but to other kind of the animal as they STILL perform regular functions. (4) Appendix is vestigial for humans, it does not perform any function but in ruminant animals it is concerned with digestion. (5) Ear muscles are vestigial for us but in monkeys and cattle they are functional. |
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| 31. |
In the electrolysis of waterName the gases liberated at anode and cathode. |
| Answer» Solution :OXYGEN is LIBERATED at the anode and hydrogen is liberated at the CATHODE | |
| 32. |
Does a prism disperse when immersed in water ? If so, how is its spectrum affected ? |
| Answer» Solution :Yes, PRISM shall DISPERSE in water. Angle of deviation gets reduced for all COLOURS if prism is immersed in water. Hence, the spectrum BECOMES NARROWER. | |
| 33. |
ISRO |
| Answer» SOLUTION :INDIAN SPACE RESEARCH ORGANIZATION. | |
| 34. |
List any five properties of light. |
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Answer» Solution :(i) Light is a form of energy . (ii) Light always TRAVELS along a STRAIGHT line. (iii) Light does not need any medium for its propagation . Itcan even travel through VACUUM. (iv) The speed of light in cacuum or air is , `c=3xx10^(8)MS^(-1)`. (v) Since , light is in the form of waves , it is characterized by a wavelegth`(lambda)` and a frequency (v) , which are ralated by the following equation : `c=vlambda` (c- velocity of light). |
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| 35. |
One word is incorrect in the statement . Change it to make the statement correct : Mammals breathe with the help of gills . |
| Answer» SOLUTION :MAMMALS breathe with the help of lungs . Or FISHES breathe with the help of GILLS . | |
| 36. |
A particle starts from origin at t=0 with velocity 5.0hati m//s and move in x.y plane under action of a force which produces a constant acceleration of (3.0hati+2.0hatj) m//s^(2). (a) What is the y-coordinate of the particle at the instant its x-ccordinate is 84 m? (b) What is the speed of the particle at this time? |
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| 37. |
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 240 resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases ? |
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Answer» Solution :V= 220 V R = 24 `Omega` (i) When TWO COILS are connected separately `I = (V)/(R) = (220)/(24)= 9.2 A ` (ii) When two coils are connected in series `R_(s)= 24 +24 = 48 Omega` `I = (V)/(R_(s))= (220)/(48) = 4.6 A ` When two coils are connected in parallel, the resistance of the combination is `(1)/(R_(p))=(1)/(24)+(1)/(24)=(1+1)/(24)=(2)/(24)=(1)/(12)` `R_(p) = 12 Omega` `I = (V)/(R_(p))=(220)/(12) = 18.3 A ` |
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| 38. |
How is heat produced by an electric current? |
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Answer» Solution :A cell or a battery is a source of electrical energy. The chemical reactions within a cell or battery generate potential DIFFERENCE between its two TERMINALS. This p.d. gets the electrons in motion, to flow through any circuit, 1.e., through a resistor or a system of RESISTORS connected to the cell or battery. So to maintain this flow, the source has to keep expending its energy. But only a part of the source energy in maintaining the current may be consumed into useful work. The rest of the source energy is converted into heat to RAISE the temperature of the electrical gadgets. |
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| 39. |
Make a lactometer with ball point refill. What would you do to make the refill stand vertically straigh ? |
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Answer» Solution :1. Take an empty BALL pen REFILL. It should have a metal point. 2. Take a BOILING tube and FILL it with water. 3. Put the refill in with metallic point inside the water. 4. Use a pen to mark the point on the refill to show the part which is above the water surface. 5. Pour out the water from the boiling tube and fill it with milk. 6. Float the refill in the milk. 7. Put the record mark on the refill, at the point showing the part which is above the surface of the milk. 8. These two marks are not at the same place. This is the improvised lactometer. 9. We have to attach a small weight at the bottom of the refill to make it stand vertically straight. 
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| 40. |
An object is placed at a distance of 30 cm from a concave lens of focal length 30 cm. (i) Use lens formula to determine the distance of the image from the lens. (ii) List four characteristics of the image (nature position, size, erect/inverted) in this case. (iii) Draw a labelled diagram to justify your answer of part (ii). |
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Answer» Solution :Object DISTANCE, `u= -30 CM,`Focal length, `f = -30 cm` (i) Lens formula, `1/f = 1/V - 1/u` So`1/v = 1/f+1/urArr 1/v= 1/-30+1/-30 =(1+1)/-30 = 2/-30` `v= -15 cm` The image distance is 15 cm in front of the lens. (ii) Characteristics of image FORMED. The image is - `*`virtual," " `*` erect," "`*`diminished, `*` in front of the lens between 'O' and 'F', and `*` 15 cm from the lens on the same side as the object (iii) 
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| 41. |
Which of the following temperatures is same on centigrade and Fahrenheit scales? |
| Answer» SOLUTION :`-40^@` | |
| 42. |
A mass of 5 kg is moving along a circular path of radius 1 m. If the mass moves with 300 rev/min. its's kinetic energy would be |
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Answer» `250pi^(2)` `V=10 pi ms^(-1)impliesK.E=1/2 mv^(2)=250pi^(2)J` |
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| 43. |
Describe briefly an activity to : (i) demonstrate the pattern of magnetic field lines around a straight current carrying conductor and, (ii) find the direction of magnetic field produced for a given direction of current in the conductor. Name and state the rule to find the direction of magnetic field around a straight current carrying conductor. Draw a diagram to explain the same activity. |
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Answer» <P> Solution : (i) (a) Take a battery (12V), a variable resistance, an ammeter (0 - SA), a plug key and a long STRAIGHT thick copper wire.(b) Insert the thick wire through the centre, normal to the plane of a rectangular cardboard. (c) Connect the copper wire vertically between X and Y as shown in series with battery, a plug key and a rheostat. (d) Sprinkle some iron fillings uniformly on the cardboard and keep the variable of the rheostat at a fixed position and note the current through the ammeter. (e) Close the key so that a current flows through the wire. Gently tap the cardboard a few times. Observe the pattern of the iron filings. (ii) To find the direction of magnetic field lines, place a compass at a point P over a circle and observe the direction of the needle. The direction of north pole of the compass WOULD GIVE the direction of magnetic field lines. Maxwell.s RIGHT Hand Thumb Rule is used to find the direction of magnetic field lines. It states that "imagine you are holding a current carrying conductor in your right hand such that the thumb points in the direction of current. Then your fingers will wrap around the conductor In the directilon of the magnetic fleldl lines." For diagram to Topic 1, LATQ , Q.1. |
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| 44. |
Waterwhichis absorbedbyrootsistransportedto aerial partsof theplantthrough |
| Answer» Answer :a | |
| 45. |
An object is placed …………. Of a convex lens to get a real image with the size of the object. |
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Answer» beyond 2`F_(1)` |
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| 46. |
Find the resistance if all of these parts are connected in :(a) Parallel(b) Series |
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Answer» SOLUTION :`because R = (rho L)/(A)`. When the conductor is cut into 4 equal parts, length of each PART `=(L)/(4)` and so resistance of each part `R_("part")=(rho(L//4))/(A)=(R )/(4)`. (a) When these 4 parts are connected in parallel then net resistance `R_(p)` is GIVEN as : `(1)/(R_(p))=(1)/((R_(1))_("part"))+(1)/((R_(2))_("part"))+(1)/((R_(3))_("part"))+(1)/((R_(4))_("part"))` `=(4)/(R )+(4)/(R )+(4)/(R )+(4)/(R )=(16)/(R )` `rArr "" R_(p)=(R )/(16)` (b)If the 4 parts are connected in SERIES then net resistance `R_(s)` is given as : `R_(s)=(R_(1))_("part")+(R_(2))_("part")+(R_(3))_("part")+(R_(4))_("part")` `=(R )/(4)+(R )/(4)+(R )/(4)+(R )/(4)=R` |
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| 47. |
Whenan iron placeis introuduced insidea current - carrying solenoidthe mangetic field of the solenoid ……… . |
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Answer» INCREASES |
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| 48. |
Explain the Myopia using the diagram. |
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Answer» Solution :1) Some PEOPLE cannot see objects at long distances but can see nearby objects clearly. This type of defect in vision is called 'Near sightedness'. 2) Myopia is corrected by using a concave lens of FOCAL length equal to the distance of the far point F from the eye. 3) This lens diverges the parallel rays from distant OBJECT as if they are coming from the far point. 4) Finally the eye lens FORMS a clear image at the RETINA. 5) Here object distance (u) is infinity and image distance (v) is equal to the far point. `u=-oo`, v=distance of far point =-D, f=focal length of bi-concave lens. We know `(1)/(f)=(1)/(v)-(1)/(u) implies (1)/(f)=-(1)/(D)impliesf=-D` Here 'f' is negative showing that it is a concave lens. 
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| 49. |
Describe an activity to show that the colours of white light splitted by a glass prism can be recombined to get white light by another identical glass prism. Also draw ray diagram to show the recombination of the spectrum of white light. |
Answer» Solution :Allowa NARROW beam of white LIGHT to fall on a PRISM `P_(1)`. The emergent light consists of seven colours and thus a SPECTRUM is formed. When a second identical prism `P_(2)` is placed in an inverted POSITION with respect to the first prism `P_(1)` as shown in Fig. 11.10, the seven coloured rays recombine to form white light again. 
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| 50. |
At noon the sun appears white as |
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Answer» light is LEAST scattered. |
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