Padhle 10th Magnetic Effects of Electric Current PDF

. adhle.i @ adhle.i Magnetic Effects of Electric C rrent CH 13 P Ca 10 No e + 10 Yea In eg a ed PYQ'. adhle.i @ adhle.i adhle.in. adhle.i @ adhle.i adhle.in  MAGNETIC EFFECTS OF ELECTRIC lumpiest...

. adhle.i @ adhle.i Magnetic Effects of Electric C rrent CH 13 P Ca 10 No e + 10 Yea In eg a ed PYQ'. adhle.i @ adhle.i adhle.in. adhle.i @ adhle.i adhle.in  MAGNETIC EFFECTS OF ELECTRIC lumpiest Oersted 's Experiment * Flans Christian Oersted , one of the leading scientists accidently discovered that a compass needle got deflected when an electric current passed through a metallic wire placed nearby. Through this Oersted that and observation showed electricity magnetism - were related phenomena. Resistor R I + - s A → Long straight 1- conductor B - O D # y K Magnetic Field : → Region around a magnet in which its force can be detected is known as magnetic field. - It has both magnitude and direction. Magnetic Field Lines : → The path along which the north pole of small magnetic compass move when placed in magnetic field. Properties of Magnetic Field Lines if They are directed from north pole to south pole outside the magnet and vice inside the versa magnet. iil Magnetic field lines are closed and curved. Magnetic field lines never intersect. iiflhe degree of closeness of the field times give the relative strength of the field lines. if If the magnetic field lines are close , the field is stronger if field , lines are far apart , magnetic field is weak. Magnetic field due to a Current - harrying Conductor 9. Magnetic field lines are concentric circles with centre at wide. 2. Magnitude of magnetic field increases if current is increased. 3. Magnitude of magnetic field decreases if we move away from wire. RIGHT FIAND THUMB Ruthie I If a current carrying conductor is imagined to be held in right hand such that thumb points in direction of current , then curled fingers of hand indicate the direction of magnetic field. - If current flows in upward direction then direction will be anticlockwise. Magnetic Field due to Current through a circular Loop * Everypoint on the wire carrying current give rise to the magnetic field appearing as a straight line at the centre of loop ,. - By applying Right Hand Thumb Rule we can find the direction of , magnetic field at every section of the wire.  Magnetic Field due to Current Carrying Solenoid Solenoid : - A coil of many circular turns of insulated copper wire wrapped closely in the shape of a cylinder is called solenoid. When electric current flows through a solenoid, magnetic field is set around solenoid similar to that of a bar magnet up. One end of a solenoid act as a north pole and other as south pole. Magnetic field is represented by straight magnet field lines parallel and very close to each other. Magnetic field inside a long solenoid decreases as we move towards ends of solenoid because magnetic field lines near the ends of solenoid start spreading out. Force On A- Current Carrying Conductor 4 Electric current flowing through a conductor produces a magnetic field. tithe field so produced exerts a force on a magnet placed in the vicinity ( nearby 134127 -4kt) of the conductor. llfrench scientist Andre Marie Ampere (9775-9836) Suggested that the magnet must also exert an equal and opposite force on the current - carrying conductor. 9. The experiment shows that the direction of force on the conductor depends upon the direction of current and the direction of the magnetic field. 2. When current carrying conductor is placed perpendicular to the direction of magnetic field the maximum displacement occurs indicating , the maximum force on the conductor. Fleming 's Left - Hand Rule → Stretch the left hand such that the thumb , first finger and Central finger are mutually perpendicular to each other. → If the first finger points in direction of magnetic field and central finger points in direction of current , then the thumb will point in direction of force.  Electric Motor * An electric motor is a rotating device that converts electrical energy to mechanical energy. - It works on the basis of rule suggested by Marie Ampere and Fleming 's left hand rule. Principle : - It is based on the principle that when a rectangular coil is placed in a magnetic field and current is passed through it , two equal and opposite forces act on the coil which rotates it continuously. Construction : It comprises : 1) Armature : → The soft iron core , on which coil is wound including the coils is called armature. - It enhances the power of the motor. ii) Commutator or split ring : → It is a device that reverses the direction of flow of current through a circuit. iii ) Magnet : → The permanent magnet ( NS) supplies the magnetic field. iv) Brush and battery. Working of electric motor : When the current begins to flow , it flows through brush X , then Ato B , B to C.Cto D and then to brush Y and into the battery. Now applying Fleming's Left Hand Rule to wire AB Current is , along AB , Magnetic Field is as shown ( North → South) the motion of the wire is downwards ,. Nowapplying Fleming 's Left Hand Rule to wire CD Current is along , CD , Magnetic field is as shown ( North South) the motion of wire is upwards → ,. The rectangular coil begins to move in the anti clockwise - direction. Note that during anti clockwise motion the split rings and - , axle also move , whereas the brushes don't move. After half a rotation Wire CD and. Split ring O moves to the left. - wire AB and Split ring P moves to the right. - Brushes X and Y do not move. Now applying Fleming 's Left Hand Rule to wire CD. Current is along DC. (Battery → Split ring → DC ,Magnetic Field is as shown ( North South) , the motion of the → wire is downwards. Now applying Fleming 's Left Hand Rule to wire AB Current is along , BA. (Battery Split → ring → DC → CB BA → Split ring P) Magnetic → , field is as shown (North-South) the motion , of wire is upwards. So again the coil rotates , in the anti clockwise - direction. The reversal of current in the coil results in the continuous rotation of the coil. The reversal of current is achieved the commutator by rings -. * The speed of rotation of the motor can be increased by : Increasing the strength of the current in the coil. Increasing the number of turns in the coil. Increasing the area of the coil. Increasing the strength of magnetic field. * In commercial motor , electromagnet instead of permanent magnet and armature. → Large number of turns of conducting wire enhances the magnetic field produced by armature. * Application of electric motor : It is used in fans , mixers , computers etc. * Electromagnetic induction : 4 When a conductor is placed in a changing magnetic field , some current is induced in it. - Such a current is called induced current and the phenomenon is called electromagnet induction. - The electricity produced as a result of induced current is called electromagnetic induction , and was discovered by Michael Faraday. Galvanometer I It is an instrument used to detect the presence of current in a circuit. - Depending upon the direction of current it. deflects either to the left to the of the or right zero mark.  Fleming 's Right Hand Rule : Electromagnetic induction can be explained with the help of Fleming 's right hand rule. Hold the thumb , the fore finger and the middle finger of right hand at right angles to each other. If the fore finger is in the direction of magnetic field and the thumb is in the direction of the motion of the conductor then the , middle finger gives the direction of the induced current. The mutually perpendicular direction also point to an important fact that when the magnetic field and movement of conductor are perpendicular , the magnitude of induced current would be maximum. Electromagnetic induction is used in the conversion of kinetic energy into electrical energy.  ​M E E C Q e i n - 1. Wha i he f nc i n f a gal an me e in a ci c i ? ​ 1M,2019 A - ​T de ec he e ence f elec ic c en in a ci c i. 2. Wh i a e ie a angemen n ed f c nnec ing d me ic elec ical a liance in a ci c i ?​ 1M,2008 A - ​A e ie a angemen i n ed f c nnec ing d me ic elec ical a liance in a ci c i beca e : (i) Same c en fl h gh each de ice, b diffe en de ice need c en f diffe en al e e a e. (ii) If ne de ice in a e ie ci c i i defec i e, c en i c ff. (iii) T al e i ance f he ci c i inc ea e , c en fl ing i ed ced. (i ) Selec i e e a i n f de ice i n ible. 3. A cha ged a icle en e a igh angle in a nif m magne ic field i h n. Wha h ld be he na e f cha ge n he a icle if i begin m e in a di ec i n in ing e icall f he age d e i in e ac i n i h he magne ic field? ​ 1M,2010 A - ​U ing Fleming lef hand le e can ea il find ha he na e f he cha ge n he a icle i i i e. 4. Define magne ic field f ba magne. ​ 1M,2015 A - ​Magne ic field a nd he ba magne i he egi n in hich magne ic f ce d e he ba magne can be e e ienced. Magne ic field line a f m he n h le and e mina e a he h le ide he magne. 5. Wha i he di ec i n f magne ic field line in ide a ba magne. ​ 1M,2017 A - ​S h le n h le. 6. Define he e m Ind ced c en. ​ 1M,2012 A - ​The c en ind ced in a c nd c ing l ha i e ed a changing magne ic field i kn n a ind ced c en. 7. Wh a e magne ic field line m e c ded ad hele f he magne ? 1M,2016 A - ​Thi indica e ha he magne ic field in ha egi n i ng​. 8. Wh d magne ic field line n in e ec ? ​ 1M,2017 A - ​The magne ic field line d n in e ec each he beca e if he d i mean a he in f in e ec he c m a needle i h ing diffe en di ec i n hich i n ible. 9. When a c en ca ing c nd c i ke in a magne ic field, a e he ii n hen ma im m f ce ac ni. ​ 1M,2014 A - ​The f ce e e ienced b a c en ca ing c nd c laced in a magne ic field i he ma im m hen he c nd c i ke e endic la he di ec i n f he magne ic field. 10. Li ce f magne ic field. ​ 1M,2012 A - ​Pe manen magne , elec magne 11. S a e he effec f a magne ic field n he a h f a m ing cha ged a icle. 1M,2012 A - ​I can deflec he a h f he cha ged a icle 12. Name he h ical an i ie hich a e indica ed b he di ec i n f he h mb and he f efinge in Fleming' igh hand le. ​ 1M,2012 A - ​In Fleming' Righ hand le, he h mb indica e M i n, he F efinge indica e Field and middle finge indica e Ind ced c en. 13. Wha i mean b he e m, magne ic field ? Wh d e a c m a needle h deflec i n hen b gh nea a ba magne ? ​ 2M,2008 A - ​Magne ic field i he egi n a nd a magne in hich a magne ic ma e ial e e ience a f ce beca e f ha magne. The needle f a c m a i ac all a mall ba magne. S , hen a c m a i b gh nea a ba magne , he c m a needle en e he magne ic field f he ba magne. The ef e, he needle e e ience a f ce beca e f he ba magne and ge deflec ed. 14. A c il f in la ed i e i c nnec ed a gal an me e. Wha ld be een if a ba magne i h i n h le a d ne face f he c il i (i) M ed ickl ad i, (ii) M ed ickl a a f m he c il and (iii) Placed nea i ne face? Name he hen mena in l ed. ​ 2M,2010 A - (​i) A m men a deflec i n in he gal an me e ill be een, indica ing a fl f c en in he ci c i. (ii) A m men a deflec i n in he gal an me e (b in i e di ec i n) ill be een, indica ing a fl f c en in he i e di ec i n in he ci c i. ​ (iii) N deflec i n in he gal an me e ill een, indica ing ha n c en fl in he ci c i. The hen men n in l ed i elec magne ic ind c i n. 15. Name and a e he le hich de e mine he di ec i n f magne ic field a nd a aigh c en ca ing c nd c. ​ 2M,2012 A - ​R H R :​ Imagine h lding he c en ca ing aigh c nd c in igh hand ch ha he h mb in a d he di ec i n f c en. Then he finge f igh hand a a nd he c nd c in he di ec i n f field line f he magne ic field. 16. When a c en ca ing c nd c i ke in a magne ic field, i e e ience a f ce. Li he fac n hich he di ec i n f hi f ce de end. ​ 2M,2013 A - ​When a c en -ca ing c nd c i laced in a magne ic field he i e e e ience a f ce d e he in e ac i n be een he field and he magne ic field d ced b he m ing cha ge in he i e. The c en ca ing c nd c gene a e i n magne ic field a nd i. Thi in e ac i h he e e nal magne ic field. When magne ic field in e ac he e ill be a ac i n and e l i n be een hem ba ed n he di ec i n f he e e nal magne ic field and he di ec i n f he c en in he c nd c. Tha i h he c nd c e e ience a f ce. 17. D a magne ic field line d ced a nd a c en ca ing aigh c nd c a ing h gh ca db a d. H ill he eng h f he magne ic field change, hen he in he e magne ic field i be de e mined i m ed a a f m he aigh i e ca ing c n an c en ? J if an e. ​ 2M,2012 A - ​U ing a c m a needle. When e m e a a f m he aigh i e, he deflec i n f he needle dec ea e hich im lie he eng h f he magne ic field dec ea e.  18. Magne ic field line a e h n in he gi en diag am. A den make a a emen ha magne ic field a X i nge han a Y. J if hi a emen. Al ed a he diag am and ma k he di ec i n f magne ic field line. 2M,2012 A - ​he ela i e eng h f he magne ic field i h n b he deg ee f cl ene f he field line. The deg ee f cl ene i m e a 'X' han a 'Y'. ∴​ The field i nge a X he e he field line a e c ded. 19. When d e h -ci c i cc ? 2M A - ​If he in la i n f he i e ed in he ci c i i damaged he a liance ed i fa l d e hich he li e i e and he ne al i e c me in di ec c n ac a a e l c en in he ci c i i e and he h ci c i cc. 20. Wha i len id? Men i n a inc ea e he eng h f he field f a len id. ​ 2M,2012 A - ​A c il f man ci c la n f in la ed c e i e a ed cl el in he ha e f a c linde i called a len id. T a inc ea e he eng h f he field f a len id : (i) B inc ea ing he n mbe f n. (ii) B inc ea ing c en. 21. (a) Di ing i h be een he e m ' e l ading' and ' h -ci c i ing' a ed in  d me ic ci c i. (b) Wh a e he c il f elec ic a e made f an all a he han a e me al? ​ 3M,2008 A - ​(a) ​ ​ - When ne al and li e i e c me in di ec c n ac. O ​ - When man a liance a e c nnec ed a ingle cke d a ing m ch m e c en e han e mi ible. (b) Re i i i f an all i highe han i c n i en me al and all d n idi e a ea il a c n i en me al a high em e a e. Tha i h he c il f elec ic a e a e made f an all a he han a e me al. 22. Wha i e l ading and h ci c i ing? Wha i he f nc i n f ea h i e? 3M,2008 A - ​If man elec ical a liance f high e a ing a e i ched n a he ame ime, he d a a la ge c en f m he ci c i. Thi i called e l ading. If he li e i e and ne al i e c me in c n ac ei he di ec l ia c nd c ing i e, he i a i n i called h ci c i ing. T a id he i k f elec ical h ck he me al b d f he a liance i ea hed. Ea hing mean c nnec he me al ca e f he a liance ea h b a mean f a me al i e called ea h i e. 23. Wha i he le f f e, ed in e ie i h an elec ical a liance? Wh h ld a f e i h defined a ing n be e laced b ne i h a la ge a ing? 3M,2017 A - ​F e i ed f ec ing a liance d e h -ci c i ing e l ading. The f e i a ed f a ce ain ma im m c en and bl ff hen a c en m e han he a ed al e fl h gh i. If a f e i e laced b ne i h la ge a ing , he a liance ma ge damaged hile he ec ing f e d e n b n ff. Thi ac ice f ing a f e f im e a ing h ld al a be a ided. 24. Name elec ical a liance f dail - e in hich elec ic m i ed. Name and a e he inci le n hich elec ic m k. ​ 3M,2012 A - ​Elec ical a liance - fan, a hing machine F ' L H R -​ I a e ha S e ch he f efinge , he cen al finge and he h mb f lef hand m all e endic la each he. If he f efinge h he di ec i n f he magne ic field and he cen al finge ha f  he c en hen he h mb ill in ad he di ec i n f m i n f he c nd c. 25. Di ing i h be een al e na ing c en and di ec c en. E lain h al e na ing c en i efe ed e di ec c en f an mi i n e l ng di ance. ​ 3M,2014 A - A.C. i efe ed e D.C. beca e i can be an mi ed e l ng di ance ih m ch l f ene g 26. (a) Wha i a magne ic field? H can he di ec i n f magne ic field line a a laced be de e mined? (b) S a e he le f he di ec i n f he magne ic field d ced a nd a c en ca ing c nd c. D a ke ch f he a e n f field line d e a c en fl ing h gh a aigh c nd c. ​ 5M,2009 A - ​(a) Magne ic field i a egi n nea a magne i ed b d he e magne ic f ce can be de ec ed. The di ec i n f he magne ic field line a a lace i de e mined b he di ec i n in hich a n h le f he c m a needle m e in ide i. (b) Di ec i n f he magne ic field d ced a nd a c en ca ing c nd c i de e mined b he igh hand h mb le. Acc ding hi le, if e h ld a c en ca ing aigh c nd c in igh hand ch ha he h mb in a d he di ec i n f c en , hen finge ill a a nd he c nd c  in he di ec i n f he field line f he magne ic field. Thi i al h n in he fig e gi en bel : Pa e n f field line d e ac en fl ing h gh a aigh c nd c : 27. (a) Wha i a len id? D a a ke ch f he a e n f field line f he magne ic field h gh and a nd a c en ca ing len id. (b) C n ide a ci c la l f i e l ing in he lane f he able. Le he c en a h gh he l cl ck i e. A l he igh hand le find he di ec i n f he magne ic field in ide and ide he l. ​ 5M,2009, 2010 A - ​(a) A len id i a l ng c il ( ha ed like a c linde ) c n aining a la ge n mbe f cl e n f in la ed c e i e. 1 (b) Di ec i n f magne ic field in ide and ide he l i gi en a f ll : 28. (a) S a e Fleming' lef hand le. (b) W i e he inci le f king f an elec ic m. (c) E lain he f nc i n f he f ll ing a f an elec ic m. (i) A ma e (ii) B he (iii) S li ing ​ 5M,2018 A - ​(a) H ld he f efinge he cen e finge and he h mb f lef hand a igh angle ne an he. If he f efinge in in he di ec i n f magne ic field, and cen e finge in in he di ec i n f c en , he h mb gi e di ec i n f m i n c nd c. (b) Elec ic m i ba ed n he inci le ha a c en ca ing c nd c laced e endic la he magne ic field e e ience a f ce. (c) (i)​ A ​ : I c n ain f a ingle l f in la ed c e i e in he f m f a ec angle. (ii)​ B ​:T ca b n b he B​1​ and B​2 ​ e again he c mm a.  The e b he ac a he c n ac be een he c mm a and he e minal f he ba e. (iii) ​ - ​:I c n i f hal e (R​1​ and R​2​) f a me allic ing. The end f he a ma e c il a e c nnec ed he e hal e f he ing. C mm a e e e he di ec i n f c en in he a ma e c il. 29. Wha i a len id? D a he a e n f magne ic field line f (i) A c en ca ing len id and (ii) A ba magne. Li di ing i hing fea e be een he field. ​ 5M,2019 A - ​A len id i a l ng c lind ical c il c n aining a la ge n mbe f cl el aced n f in la ed c e i e. Di ing i h be een he field a e (a) The eng h f magne ic field d e len id can be changed hile he magne ic field eng h d e ba magne cann be changed. (b) S len id d ce magne ic field l ng a c en fl in i c il hile ba magne d ce a e manen magne ic field. 30. De c ibe an fi e afe mea e ha h ld be aken hile dealing i h elec ical a liance c nnec ed in d me ic elec ic ci c i. ​ 5M,2013 A - ​(i) T a id h ck f m elec ical a liance , e e -ea hing a angemen. (ii) Re lace ld n and damaged i e i h a ne e. (iii) P he main i ch ff hen em ing an fa l in elec ic ci c i. (i ) Wea bbe h e and gl e hile dealing i h e lacemen f an a liance. ( )D n hand in ide a e being hea ed i h an imme i n d, hen he d i in ide and n.