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2 Hed Office : B-3, Shivlik Min Rod, Mlviy Ngr, New Delhi-7 Sles Office : B-48, Shivlik Min Rod, Mlviy Ngr, New Delhi-7 Tel. : -669 / D.P. Gup (Mhemics) Preeim Bjpi (Chemisry) Snjeev Kumr Jh (Physics) Price : ` 45 Typese by Dish DTP Tem DISHA PUBLICATION ALL RIGHTS RESERVED Publisher No pr of his publicion my be reproduced in ny form wihou prior permission of he publisher. The uhor nd he publisher do no ke ny legl responsibiliy for ny errors or misrepresenions h migh hve crep in. We hve ried nd mde our bes effors o provide ccure up-o-de informion in his book. For furher informion bou he books from DISHA, Log on o or emil o info@dishpublicion.com

3 CONTENT PHYSICS P- P-. Physicl World, Unis nd Mesuremens -4. Moion in Srigh line 5-3. Moion in Plne Lws of Moion Work, Energy nd Power Roionl Moion Grviion Mechnicl Properies of Solids Mechnicl Properies of Fluids Therml Properies of Mer Thermodynmics Kineic Theory Oscillions 9-4. Wves Elecric Chrges nd Fields Elecrosic poenil nd cpcince Curren Elecriciy Moving Chrges nd Mgneism Mgneism nd Mer Elecromgneic Inducion Alerning Curren Elecromgneic Wves Ry Opics nd Opicl Insrumens Wve Opics Dul Nure of Rdiion nd Mer Aoms Nuclei 5-8. Semiconducor Elecronics : Merils, Devices nd Simple Circuis Communicion Sysems - CHEMISTRY C- C-6. Some Bsic Conceps of Chemisry -5. Srucure of Aom 6-3. Clssificion of Elemens nd Periodiciy in Properies Chemicl Bonding nd Moleculr Srucure Ses of Mer Thermodynmics Equilibrium Redox Recions Hydrogen 5-5

4 . The s-block Elemens The p-block Elemens (Group-3 nd 4) Orgnic Chemisry Some Bsic Principles & Techniques Hydrocrbons Environmenl Chemisry The Solid Se Soluions Elecrochemisry Chemicl Kineics Surfce Chemisry 3-5. Generl Principles nd Processes of Isolion of Elemens 6-7. The p-block Elemens (Group 5, 6, 7 & 8) 8-. The d-nd f-block Elemens Co-ordinion Compounds Hlolknes nd Hlorenes Alcohols, Phenols nd Ehers Aldehydes, Keones nd Crboxylic Acids Amines Biomolecules Polymers Chemisry in Everydy Life Anlyicl Chemisry 59-6 MATHEMATICS M- M-4. Ses -. Relions nd Funcions Trigonomeric Funcions 5-4. Principle of Mhemicl Inducion - 5. Complex Numbers nd Qudric Equions Liner Inequliy Permuions nd Combinions Binomil Theorem Sequence nd Series Srigh Lines & Pir of Srigh Lines Conic Secions Limis nd Derivives Mhemicl Resoning Sisics Probbiliy 8-6. Relions nd Funcions Inverse Trigonomeric Funcions 9-8. Mrices Deerminns Coninuiy nd Differenibiliy Applicion of Derivives Inegrls Applicions of Inegrls Differenil Equions Vecor Algebr Three Dimensionl Geomery Probbiliy Properies of Tringle 36-4

5 Physicl World, Unis nd Mesuremens P- Chper PHYSICS Physicl World, Unis nd Mesuremens. Idenify he pir whose dimensions re equl [] orque nd work sress nd energy force nd sress force nd work. Dimensions of moeo, where symbols hve heir usul mening, re [3] [L - T] - [L T ] - [L T ] - [LT ] 3. The physicl quniies no hving sme dimensions re orque nd work [3] momenum nd plnck s consn sress nd young s modulus -/ speed nd ( mo eo ) 4. Which one of he following represens he correc dimensions of he coefficien of viscosiy? [4] éml T ë - - ù û émlt - ù é - - ML T ù é - - ML T ù 5. Ou of he following pir, which one does NOT hve idenicl dimensions? [5] Impulse nd momenum Angulr momenum nd plnck s consn Work nd orque Momen of ineri nd momen of force 6. The dimensions of mgneic field in M, L, T nd C (coulomb) is given s [8] [MLT C ] [MT C ] [MT C ] [MT C ] 7. A body of mss m 3.53 kg is moving long he x-xis wih speed of 5. ms. The mgniude of is momenum is recorded s [8] 7.6 kg ms kg ms 7.56 kg ms 7.57 kg ms 8. Two full urns of he circulr scle of screw guge cover disnce of mm on is min scle. The ol number of divisions on he circulr scle is 5. Furher, i is found h he screw guge hs zero error of.3 mm. While mesuring he dimeer of hin wire, suden noes he min scle reding of 3 mm nd he number of circulr scle divisions in line wih he min scle s 35. The dimeer of he wire is [8] 3.3 mm 3.73 mm 3.67 mm 3.38 mm 9. In n experimen he ngles re required o be mesured using n insrumen, 9 divisions of he min scle excly coincide wih he 3 divisions of he vernier scle. If he smlles division of he min scle is hlf- degree (.5 ), hen he les coun of he insrumen is: [9] hlf minue one degree hlf degree one minue. The respecive number of significn figures for he numbers 3.3,.3 nd. 3 re [] 5,, 5,, 5 5, 5, 4, 4,. A screw guge gives he following reding when used o mesure he dimeer of wire. Min scle reding : mm Circulr scle reding : 5 divisions Given h mm on min scle corresponds o divisions of he circulr scle. The dimeer of wire from he bove d is [].5 cm.6 cm.5 cm.5 cm. Resisnce of given wire is obined by mesuring he curren flowing in i nd he volge difference pplied cross i. If he percenge errors in he mesuremen of he curren nd he volge difference re 3% ech, hen error in he vlue of resisnce of he wire is [] 6% zero % 3% 3. A specromeer gives he following reding when used o mesure he ngle of prism. Min scle reding : 58.5 degree Vernier scle reding : 9 divisions Given h division on min scle corresponds o.5 degree. Tol divisions on he Vernier scle is 3 nd mch wih 9 divisions of he min scle. The ngle of he prism from he bove d is [] degree degree degree 59 degree 4. Given h K energy, V velociy, T ime. If hey re chosen s he fundmenl unis, hen wh is dimensionl formul for surfce ension? [Online My 7, ] [KV T ] [K V T ] [K V T ] [KV T ] 5. A suden mesured he dimeer of wire using screw guge wih he les coun. cm nd lised he mesuremens. The mesured vlue should be recorded s [Online My, ] 5.3 cm 5.3 cm 5.3 cm 5.3 cm

6 P- Physics 6. N divisions on he min scle of vernier clliper coincide wih (N + ) divisions of he vernier scle. If ech division of min scle is unis, hen he les coun of he insrumen is [Online My 9, ] N N N + N + 7. Le [ Î ] denoe he dimensionl formul of he permiiviy of vcuum. If M mss, L lengh, T ime nd A elecric curren, hen: [3] Î [M L 3 T A] Î [M L 3 T 4 A ] Î [M L T A ] Î [M L T A] 8. The dimensions of ngulr momenum, len he nd cpcince re, respecively. [Online April, 3] MLTA,LT,M L T MLT,LT,M L T A - - MLT,LT,MLTA of lengh L. In his experimen ime for oscillions is mesured by using wch of second les coun nd he vlue is 9. seconds. The lengh L is mesured by using meer scle of les coun mm nd he vlue is. cm. The error in he deerminion of g would be: [Online April 9, 4].7%.7% 4.4%.7% 3. In erms of resisnce R nd ime T, he dimensions of rio m of he permebiliy m nd permiiviy e is: e [Online April, 4] [RT ] [R T ] [R ] [R T ] 4. From he following combinions of physicl consns (expressed hrough heir usul symbols) he only combinion, h would hve he sme vlue in differen sysems of unis, is: [Online April, 4] ch pe o e peogme me G o o c he (m e mss of elecron) MLT,LT,M L TA 9. If he ime period of he oscillion of drop of liquid of densiy d, rdius r, vibring under surfce ension s is given by he formul b c / r s d. I is observed h he ime period is direcly proporionl o d. The vlue of b s should herefore be : [Online April 3, 3] The curren volge relion of diode is given by V T ( ) I e - ma, where he pplied volge V is in vols nd he emperure T is in degree kelvin. If suden mkes n error mesuring ±.V while mesuring he curren of 5 ma 3 K, wh will be he error in he vlue of curren in ma? [4]. ma. ma.5 ma.5 ma. A suden mesured he lengh of rod nd wroe i s 3.5 cm. Which insrumen did he use o mesure i? [4] A meer scle. A vernier clliper where he divisions in vernier scle mches wih 9 division in min scle nd min scle hs divisions in cm. A screw guge hving divisions in he circulr scle nd pich s mm. A screw guge hving 5 divisions in he circulr scle nd pich s mm.. An experimen is performed o obin he vlue of ccelerion due o grviy g by using simple pendulum 3 3 p me o o h ce G 5. In he experimen of clibrion of volmeer, sndrd cell of e.m.f.. vol is blnced gins 44 cm of poenil wire. The poenil difference cross he ends of resisnce is found o blnce gins cm of he wire. The corresponding reding of volmeer is.5 vol. The error in he reding of volmeer will be: [Online April, 4]. 5 vol.5 vol.5 vol.5 vol 6. Mch Lis - I (Even) wih Lis-II (Order of he ime inervl for hppening of he even) nd selec he correc opion from he opions given below he liss: [Online April 9, 4] Lis - I () Roion period of erh () Revoluion period of erh (3) Period of ligh wve (4) Period of sound wve (i) 5 s (ii) 7 s (iii) 5 s (iv) 3 s Lis - II ()-(i), ()-(ii), (3)-(iii), (4)-(iv) ()-(ii), ()-(i), (3)-(iv), (4)-(iii) ()-(i), ()-(ii), (3)-(iv), (4)-(iii) ()-(ii), ()-(i), (3)-(iii), (4)-(iv)

7 Physicl World, Unis nd Mesuremens P-3 Hins & Soluions r. r W F s Fs cosq - - [ MLT ][ L] [ MLT ]; r r F r Þ rf sinq - - [ L][ MLT ] [ ML T ]. We know h he velociy of ligh in vcuum is given by c me o o \ moeo c L T 3. Momenum mv [MLT ] Plnck s consn, E [ MLT ] - h [ MLT ] v [ T ] 4. From Sokes lw, F 6phrv Þ h F 6prv - [ MLT ] \ h Þh ML T [ L][ LT ] 5. Momen of Ineri, I Mr [ ] [I] [ ML ] Momen of force, r uur uur r F r éù - - [ L][ MLT ] [ MLT ] 6. We know h F q v B - F MLT - - \ B MT C qv - C LT 7. Momenum, p m v (3.53) (5.) kg m/s 7.6 (Rounding off o ge hree significn figures) 8. Les coun of screw guge.5 mm.mm 5 \ Reding [Min scle reding + circulr scle reding L.C] (zero error) [ ] (.3) 3.38 mm 9. 3 Divisions of vernier scle coincide wih 9 divisions of min scles Therefore V.S.D 9 3 MSD Les coun MSD VSD 9 MSD - MSD 3 MSD 3.5 minue. 3. Number of significn figures in Number of significn figures in.3 Number of significn figures in. 3 So, he rdiion belongs o X-rys pr of he specrum.. L.C. mm Dimeer of wire MSR + CSR L.C.. V R I Þ mm.5 cm V±DV R±D R I±DI æ ö DR V ç ±DV/ V æ ö Rç ± è R ø ç I DI ç ± è I ø ædrö ç è R ø æ D Vö æ D I ö ç + ç (3 + 3)% 6% è V ø è I ø 3. Q Reding of Vernier Min scle reding + Vernier scle reding les coun. Min scle reding 58.5 Vernier scle reding 9 division les coun of Vernier.5 /3 Thus, R R F F l T 4. Surfce ension, T.. l l l T T - (As, F.l K (energy); V ) l Therefore, surfce ension [KV T ] 5. The les coun (L.C.) of screw guge is he smlles lengh which cn be mesured ccurely wih i. As les coun is. cm cm Hence mesured vlue should be recorded upo 3 deciml plces i.e., 5.3 cm 6. No of divisions on min scle N No of divisions on vernier scle N + size of min scle division Le size of vernier scle division be b hen we hve N N b (N + ) Þ b N + N Les coun is b N+ én + -Nù ê N + ú N +

8 P-4 Physics 7. As we know, qq F Þ 4 pe R qq e 4 p FR C [AT] Hence, e - N.m MLT.L [M L T A ] 8. Angulr momenum m v r ML T - Q MLT Len he L L T m M Chrge - - Cpcince C M L TA P.d. 9.. The curren volge relion of diode is VT / ( -) I e ma (given) When, VT / I 5 ma, e 6mA V / T Also, di ( e ) 4 T (By exponenil funcion) (6 ma ) (.). ma 3. Mesured lengh of rod 3.5 cm For vernier scle wih Min Scle Division mm 9 Min Scle Division Vernier Scle Division, Les coun MSD VSD. mm. According o he quesion. Þ (9 ± ) or, l ( ±.) or, Dg g %? As we know, p l g 4p l g D 9 D l l or, D g æ D l D ö ± ç + è g l ø æ. ö ç + è 9 ø.7. \ Dg %.7% g 3. Dimensions of m [MLT A ] Dimensions of Î [M L 3 T 4 A ] Dimensions of R [ML T 3 A ] \ Dimensionsof - - m Dimensions of Î [MLT A ] [M L T A ] [M L 4 T 6 A 4 ] [R ] 4. The dimensionl formule of e ém LTA ù e ém LTA ù G ém LT ù nd me émlt ù e Now, pe Gm e émltaù pém L T A ùém L T ùém L T ù ét A ù pém L T A ë ù û é T A ù pém L T A ù p Q p is dimensionless hus he combinion e pegme would hve he sme vlue in differen sysems of unis. 5. In volmeer Þ V µ l V kl Now, i is given E. vol for l 44 cm nd V.5 vol for l cm Le he error in reding of volmeer be DV hen,. 4 K nd (.5 DV) K...5 -DV 44 \ D V -.5 vol 6. Roion period of erh is bou 4 hrs ; 5 s Revoluion period of erh is bou 365 dys ; 7 s Speed of ligh wve C 3 8 m/s Wvelengh of visible ligh of specrum l 4 78 Å C f l æ ö ç nd T è f ø Therefore period of ligh wve is 5 s (pprox)

9 Moion in Srigh line P-5 Chper Moion in Srigh line. If body looses hlf of is velociy on penering 3 cm in wooden block, hen how much will i penere more before coming o res? [] cm cm 3 cm 4 cm.. Speeds of wo idenicl crs re u nd 4u he specific insn. The rio of he respecive disnces in which he wo crs re sopped from h insn is [] : : 4 : 8 : 6 3. From building wo blls A nd B re hrown such h A is hrown upwrds nd B downwrds (boh vericlly). If v A nd v B re heir respecive velociies on reching he ground, hen [] v B > v A v A v B v A > v B heir velociies depend on heir msses. 4. A cr, moving wih speed of 5 km/hr, cn be sopped by brkes fer les 6 m. If he sme cr is moving speed of km/hr, he minimum sopping disnce is [3] m 8 m 4 m 6 m 5. A bll is relesed from he op of ower of heigh h meers. I kes T seconds o rech he ground. Wh is he posiion of he bll 3 T second [4] 8h meers from he ground 9 7h meers from he ground 9 h meers from he ground 9 7h meers from he ground 8 6. r r r r If A B B A, hen he ngle beween A nd B is [4] p p 3 p 7. An uomobile rvelling wih speed of 6 km/h, cn brke o sop wihin disnce of m. If he cr is going wice s fs i.e., km/h, he sopping disnce will be [4] 6 m 4 m m 8 m p 4 8. A cr, sring from res, cceleres he re f hrough disnce S, hen coninues consn speed for ime nd hen deceleres he re f o come o res. If he ol disnce rversed is 5 S, hen [5] S S 6 f S f 4 f S 7 f 9. A pricle is moving eswrds wih velociy of 5 ms. In seconds he velociy chnges o 5 ms norhwrds. The verge ccelerion in his ime is [5] - ms owrds norh - ms owrds norh - es - ms zero owrds norh - wes. The relion beween ime nd disnce x is x + bx where nd b re consns. The ccelerion is [5] 3 bv - bv v 3 -v. A pricle loced x ime, srs moving long wih he posiive x-direcion wih velociy 'v' h vries s v x. The displcemen of he pricle vries wih ime s [6] / 3. The velociy of pricle is v v + g + f. If is posiion is x, hen is displcemen fer uni ime ( ) is [7] v + g / + f v + g + 3f v + g / + f/3 v + g + f 3. A body is res x. A, i srs moving in he posiive x-direcion wih consn ccelerion. A he sme insn noher body psses hrough x moving in he posiive x-direcion wih consn speed. The posiion of

10 P-6 Physics he firs body is given by x () fer ime ; nd h of he second body by x () fer he sme ime inervl. Which of he following grphs correcly describes (x x ) s funcion of ime? [8] y h ( x x ) ( x x ) O O v v ( x x ) ( x x ) O O O y h 4. Consider rubber bll freely flling from heigh h 4.9 m ono horizonl elsic ple. Assume h he durion of collision is negligible nd he collision wih he ple is olly elsic. Then he velociy s funcion of ime nd he heigh s funcion of ime will be : [9] v +v O v y v +v h O v 4 5. An objec, moving wih speed of 6.5 m/s, is decelered re given by dv -.5 v where v is he insnneous speed. The ime d ken by he objec, o come o res, would be: [] s 4 s 8 s s 6. A cr of mss kg is moving speed of 3 m/s. Brkes re pplied o bring he cr o res. If he ne rerding force is 5 N, he cr comes o sop fer rvelling d m in s. Then [Online My 7, ] d 5, 5 d, 8 d 8, 6 d 9, 6 7. The grph of n objec s moion (long he x-xis) is shown in he figure. The insnneous velociy of he objec poins A nd B re v A nd v B respecively. Then [Online My 7, ] x(m) 5 y h 5 D 8 B A Dx 4 m O (s) v A v B.5 m/s v A.5 m/s < v B v A.5 m/s > v B v A v B m/s

11 Moion in Srigh line P-7 8. The disnce rvelled by body moving long line in ime is proporionl o 3. The ccelerion-ime (, ) grph for he moion of he body will be [Online My, ] 9. A goods rin ccelering uniformly on srigh rilwy rck, pproches n elecric pole snding on he side of rck. Is engine psses he pole wih velociy u nd he gurd s room psses wih velociy v. The middle wgon of he rin psses he pole wih velociy. [Online My 9, ] u+ v uv u + v æ u + v ö ç è ø. From ower of heigh H, pricle is hrown vericlly upwrds wih speed u. The ime ken by he pricle, o hi he ground, is n imes h ken by i o rech he highes poin of is ph. The relion beween H, u nd n is:[4] gh n u ( - ) gh n ud gh nu ( n - ) gh ( n-) u. A person climbs up slled esclor in 6 s. If snding on he sme bu esclor running wih consn velociy he kes 4 s. How much ime is ken by he person o wlk up he moving esclor? [Online April, 4] 37 s 7 s 4 s 45 s

12 P-8 Physics Hins & Soluions. Aciviy A o B u u ; v u, s.3 m,? - v u s...(i) u A æuö \ ç è ø u/ 3 cm B C - speed u.3 u Þ 4-3 u.6 Þ - u Þ u 4.6 Aciviy B o C: Assuming he sme rerdion u u / ; v ; s? ; - v u s...(ii) u æ -3 u ö \ - ç s 4 è4.6ø -3 u 4.6 Dividing (i) nd (ii), u 6u s s Þ 6 s s 3. Bll A is hrown upwrds from he building. During is downwrd journey when i comes bck o he A u poin of hrow, is speed is equl o he speed of hrow. So, for he journey of boh he blls from poin h A o B. B We cn pply v u gh. As u, g, h re sme for boh he blls, v A v B 4. 5 Cse- : u 5 m / s, 8 v,s 6m, v - u s ö Þ - ç 5 6 è 8ø æ 5 æ 5ö Þ - ç (i) è 8ø Cse- : u km/hr 5 m/sec 8 u Þ s m cm Alernively, dividing (i) nd (ii), - -u s v u s v æuö ç -u èø.3 Þ Þ s cm. æuö s -ç è ø. For cr u u, v,, s s \ - v u s Þ u s Þ u s...(i) For cr u 4u, v,, s s \ - v u s Þ (4u) ( ) s Þ 6 u s...(ii) v, s s, \ v - u s æ 5 ö Þ - ç s è 8ø æ 5ö Þ - ç s è 8ø Dividing (i) nd (ii) we ge s We hve s u + g, or h (ii) Þ s 4m gt (Q u ) now for T/3 second, vericl disnce moved is given by æ ' T ö h gç Þ h' gt h è 3ø 9 9

13 Moion in Srigh line P-9 h \ posiion of bll from ground h - 9 r r r r r r r r 6. A B- B A Þ A B+ A B 8h 9 D v v + (-v) v N r r \ A B Angle beween hem is, p, or p from he given opions, q p W 9 - v v E Speed, u 6 m/s m/s d m, u' m / s 8 3 Le declrion be hen () u d or u d () nd () u' d' or u ' d ' () () divided by () gives, d ' 4 Þ d ' 4 8m d 8. Disnce from A o B S f Disnce from B o C ( f ) Disnce from C o D ( f ) f S u ( f / ) A f B C f / D Þ 5 S S + f + S 5S Þ f S... (i) f S... (ii) Dividing (i) by (ii), we ge 6 Þ f S f æ ç ö è 6ø 7 9. Averge ccelerion chngein velociy ime inervl D v uur. uur uur v 5 iˆ, v 5ˆj uur ur ur D v ( v -v) S v + v+ vv cos [As v v 5 m/s] 5 m / s Avg. cc. Dv uur 5 m /s n 5 q which mens q is in he second qudrn. (owrds norh -wes) x + bx ; Diff. wih respec o ime () d d dx dx ( ) ( x ) + b.x +b.v. d d d d xv + bv v (x + b)(v velociy) x + b v. Agin differeniing, dx + - d v Þ dv d f. v x, x dx ò d x ò dv d 3 - v x é xù ê ú [] ë û Þ x æ dx ö ç Q v è d ø dx x d Þ dx d x Þ x 4

14 P- Physics dx. We know h, v Þ dx v d d Inegring, or x dx v d ò ò x ò( v + g + f ) d é 3 g f ù êv + + ú êë 3 úû As increses, v decreses. We ge srigh line beween v nd wih negive slope. Also y u - g All hese chrcerisics re represened by grph. dv v d Þ dv v Inegring,.5 d -½ v dv ò d ò or, 3 g f x v g f A, x v For he body sring from res x + x x Þ x For he body moving wih consn speed x v \ x- x -v, x x v/ For < v ; he slope is negive For v ; he slope is zero For > v ; he slope is posiive These chrcerisics re represened by grph. 4. For downwrd moion v g The velociy of he rubber bll increses in downwrd direcion nd we ge srigh line beween v nd wih negive slope. Also pplying y- y u + We ge y - h - g Þ y h - g The grph beween y nd is prbol wih y h. As ime increses y decreses. For upwrd moion. The bll suffer elsic collision wih he horizonl elsic ple herefore he direcion of velociy is reversed nd he mgniude remins he sme. Here v u g where u is he velociy jus fer collision. ½ é + v ù êë (½) úû6.5 Þ ê ú -.5[] Þ (6.5) ½.5 Þ sec 6. Given: mss of cr m kg u 3 m/s v m/s rerding force f 5 N \ rerdion, 5 5 m/s By equion, v u s (3) 5 d \ d 9 9 m - nd v u - \ v u - 3 6s Dx Insnneous velociy v D DxA 4m From grph, va.5 m/s DA 8s DxB 8m nd v B.5 m/s D 6s B i.e., v A v B.5 m/s 8. Disnce long line i.e., displcemen (s) 3 (Q 3 s µ given) By double differeniion of displcemen, we ge ccelerion. 3 ds d V 3 d d nd dv d3 6 d d 6 or µ Hence grph is correc.

15 Moion in Srigh line P- 9. Le 'S' be he disnce beween wo ends '' be he consn ccelerion As we know v u S or, S v -u Le v be velociy mid poin. Therefore, vc u + S v -u vc u + v c u S vc - u + v. Speed on reching ground v u + gh Now, v u + H u Þ u + gh - u + g u Time ken o rech highes poin is, g u + u +gh nu Þ (from quesion) g g Þ gh n(n )u. Person s speed wlking only is "esclor" 6 second Snding he esclor wihou wlking he speed is "esclor" 4 second Wlking wih he esclor going, he speed dd. So, he person s speed is 5 + "esclor" 6 4 second So, he ime o go up he esclor 4 second. 5

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