JEE Main Online Exam 2019

Transcription

1 JEE Min Online Ex 09 [Meory Bse Pper] uestions & Answer 9 th Jnury 09 Shift - I PHYSICS. Deterine the tio of root en squre spee of Heliu to Aron s t the se teperture (M He = 4U & M Ar = 40 U) () 0 () Ans. []. A oop ABCD hve current i = 0A s shown in fiure. AB & CD re rc of rius c & c espectively eterine netic fiel intensity t O. O c 4 A B c 00 π 0 7 T Ans. [] D () 00 π 0 7 T i C 7 () 00π 0 T 00π 0 T 7. A point object is plce in front of lens t istnce 0 c fro convex lens. ens prouces shrp ie t screen locte t 0 c fro lens. Now lss slb of refrctive inex. & thicness. c is plce in contct with lens t its left sie. Now in orer to et shrp ie in on the screen by wht istnce screen shoul be shifte. 0. () 0. () 0.4 None Ans. [] CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph:

2 .4 Deterine iniu vlue of force require to eep bloc in equilibriu. N 4 0 μ = 0.6 N () 8 N () N N. Point chre in fixe on (, 0, 0) nother chre is plce t (0, 0, 0). Wht shoul be the vlue of q so tht t oriin will be in equilibriu. Ans. [4] 4 q () () 4.6 In the iven circuit eterine the vlue of i? Ω 4Ω 0 V 0 V i i Ω i 4A () A () 0 A A Ans. [].7 A loop whose re is 0 n resistnce is 0 Ω. Mnetic fiel 0.4 sin (0πt) T is present perpeniculr to loop then inuce chre flow in loop in tie t = 0 to t = 0 s will be 0 4 () 0 4 () 0 4 None.8 In Interference between two liht wves of intensity I & I, the rtio of xiu n iniu intensity in Interference pttern is 6 :. Deterine the rtio I : I () () CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph:

3 .9 shpe ro is hine fro O in verticl plne t its one en s shown in fiure. o is in equilibriu position then. Deterine φ. φ tn () tn () 4 π None.0 iht of wvelenth λ l = 0 n n λ = 40 n is incient one by one on etl plte. The rtio of xiu spee of ejecte photoelectron is v : v = :. Deterine the wor function of etl. ev ().9 ev ().6 ev. ev Ans. []. A conuctor of iven shpe hs teperture ifference of 0 C cross ens A & B. Whole conuctor is of unifor cross sectionl re n unifor therl conuctivity. in the teperture between C & D t stey stte. l l/4 A B l/ C D l/ 0 () 60 () 4. Uniforly chre insultin rin of rius is iven s shown in fiure. Deterine the istnce h fro centre lon the xis of rin t which electric fiel intensity is xiu. xis () () CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph:

4 . iht is incient t wter ir interfce s shown in fiure. efrctive inex of slb is μ =.. Deterine the iniu vlue of refrctive inex of wter for which fter striin t wter slb interfce finl eerent liht is copletely polrise liht. Wter Glss μ =. 4 () 7 () 6.4 A bloc of ss M is suspene with unifor strin of ss t cellin of crt s shown in fiure. Velocity of wve pulse in strin t its lowest point strin is 60 /s. Now cr oves with ccelertion /s in horizontl irection then velocity of wve pulse t se point is 60. /s. in the vlue of ccelertion. M 0 () 0 () 40 Ans. []. enth of conuctin wire is increse by 0.% eepin its volue constnt. Deterine the percente chne in resistnce of wire. % () % () % 4%.6 A bloc rest on sooth surfce ttche with sprin s shown sprin is in nturl lenth, if constnt force pplie on bloc in rihtwr irection then fin xiu velocity of bloc? () () CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph:

5 .7 A ro of torsionl constnt is ttche to centre of sses of two point ss connecte by ssless ro t point P s shown in fi. If ro is twiste by sll nle Δθ n relese, fin its nulr frequency? / P COM ro ( Δθ) l () ( Δθ) l () ( Δθ) l 6( Δθ) l.8 Erth is revolvin roun sun with nulr oentu then eterine the eril velocity of erth. (ss of erth is ) () () 4 Ans. [].9 our colour bn resistor with colours of bn is iven in fiure. Wht is the vlue of resistnce of resistor. e violet orne silver 7 0 ± % () 6 0 ± % () 7 0 ± 0% 6 0 ± 0 %.0 Initilly Bloc 'A' is iven horizontl velocity V n other bloc B & C re t rest. All possible collision re perfectly inelstic collision. Totl enery loss fter ll collisions is 6 ties of initil inetic enery of syste. in : M. 4 v M A B C () () 4 4 r. A prticle is ovin in xy plne with velocity v = yî xĵ. Deterine eqution of pth of prticle. Hyperbol () Ellipse () Prbol Striht line CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph:

6 . A Iel s is ten fro stte A to stte C By two ifferent processes ABC & ADC s shown in PV rph. Het supplie to the s in ABC process is 60 Joule while wor one by s in se process is 0 joule. If wor one by s in ADC process is 0 joule. Deterine het supplie to s in process ADC. P B C A D V 40 J () 0 J () 60 J 0 J. An infinitely lon striht wire crryin current I is plce in the plne of circulr coil of rius crryin current I. If wire is t istnce fro centre of coil ( >> ), then the force exerte by wire on coil is proportionl to - () () zero.4 A wire of teril of cross sectionl re A n lenth l is hete to increse its teperture By ΔT. Teperture coefficient of liner expnsion of teril = α C. orce is pplie t the ens of wire so tht it lenth o not increse on hetin. Deterine youn oulus of teril of wire. () () αδta αaδt AαΔT AαΔT. In electronetic wve, electric fiel vector E = 6 ĵ N/C is iven. Deterine netic fiel intensity vector B. requency of Electro netic wve = 0 MHz. 0 8 ˆ T () 8 0 ˆ T 8 8 () 0 ˆ T 4 0 ˆ T Ans. [].6 Dielectric of ielectric constnt is present between the pltes of cpcitor s shown in fiure. Deterine the cpcitnce of prllel plte cpcitor. (Pltes of cpcitor re squre of with ) 0 () 0 () 0 0 ( ) ( ) ( ) ( ) CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph:

7 .7 There is current of.44 p in copper wire whose re of cross section norl to the lenth of the wire is. If the nuber of free electrons per c is 8.4 0, then the rift velocity woul be.0 /s ().0 /s () 0. /s 0.0 /s.8 If the electron ensity of N-type seiconuctor is 0 per c n the obility of the electron s μ e = 00 c /V-S. The vlue of resistivity of n-type seiconuctor is -. Ω-c (). Ω- (). Ω-c. Ω- Ans. [].9 A rio ctive sple S hvin n ctivity of μci hs twice the nuber of nuclei s nother sple S which hs n ctivity of 0μCi. The hlf lives of S & S cn be 0 ys n ys respectively () 0 ys n 0 yers, respectively () 0 yers ech yers ech.0 The coercivity of sll net where the ferronet ets enetize is 0 A. The current require to be psse in solenoi of lenth 0 c n nuber of turns 00, so tht the net ets enetize when insie the solenoi, is - 60 A () A () 6 A 0 A Ans. [] CAEE POINT t., CP Tower, IPIA, o No., Kot (j.), Ph: