Practice Questions
1,025 questions across 23 years of JEE Main β find and practise any topic!
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Q16.The magnetic field vector of an electromagnetic wave is given by π΅= π΅0 ^i β2 represents unit vector along π₯ and π¦-axis respectively. At π‘= 0 s, two electric charges π1 of 4π coulomb and π 3π of 2π coulomb located at 0, 0, and 0, 0, respectively, have the same velocity of 0 . 5c ^i, (where π2 π π, π is the velocity of light ). The ratio of the force acting on charge π1 to π2 is : (1) 1 : β2 (2) 2β2 : 1 (3) β2 : 1 (4) 2 : 1
Q17.There are two infinitely long straight current-carrying conductors and they are held at right angles to each other so that their common ends meet at the origin as shown in the figure given below. The ratio of current in both conductors is 1: 1. The magnetic field at point π is_________ . (1) π0I + π¦2 - (π₯+ π¦) (2) π0Iπ₯π¦ βπ₯2 + π¦2 - (π₯+ π¦) 4Οxyβπ₯2 4Ο (3) π0I + π¦2 + (π₯+ π¦) (4) π0Iπ₯π¦ βπ₯2 + π¦2 + (π₯+ π¦) 4Οxyβπ₯2 4Ο
Q35.Which of the following equation depicts the oxidizing nature of H2O2 ? (1) 2Iβ+ H2O2 + 2H+ βI2 + 2H2O (2) I2 + H2O2 + 2 OHββ2Iβ+ 2H2O + O2 (3) Cl2 + H2O2 β2HCl + O2 (4) KIO4 + H2O2 βKIO3 + H2O + O2
Q36. Correct statement about the given chemical reaction is (1) Reaction is possible and compound (A) will be (2) βΒ¨NH2 group is ortho and para directive, so major product. product (B) is not possible. (3) Reaction is possible and compound (B) will be (4) The reaction will form sulphonated product the major product. instead of nitration.
Q37.What is the correct sequence of reagents used for converting nitrobenzene into m -dibromobenzene? (1) Sn / HCl KBr Br2 H+ (2) Br2 / Fe Sn / HCl NaNO2 / HCl CuBr / HBrβββββββ / β / β/ β β / β / β / β (3) NaNO2 HCl KBr H+ (4) Sn / HCl Br2 NaNO2 NaBrβββββββ / β / β / β β / β/ β / β
Q38.The correct sequence of correct reagents for the following transformation is :- (1) (i) Fe, HCl (2) (i) Fe, HCl (ii) Cl2, HCl, (ii) NaNO2, HCl, 0Β°C (iii) NaNO2, HCl, 0Β°C (iii) H2O/H+ (iv) H2O/H+ (iv) Cl2, FeCl3 (3) (i) Cl2, FeCl3 (4) (i) Cl2, FeCl3 (ii) Fe, HCl (ii) NaNO2, HCl, 0Β°C (iii) NaNO2, HCl, 0Β°C (iii) Fe, HCl (iv) H2O/H+ (iv) H2O/H+
Q38.The correct sequence of reagents used in the preparation of 4 -bromo- 2-nitroethylbenzene from benzene is : JEE Main 2021 (25 Feb Shift 2) JEE Main Previous Year Paper (1) CH3 COCl / AlCl3, Br2 / AlBr3, HNO3 /H2 SO4, Zn / HCl (2) CH3 COCl / AlCl3, Zn βHg / HCl, Br2 / AlBr3, HNO3 /H2 SO4 (3) HNO3 /H2 SO4, Br2 / AlCl3, CH3 COCl / AlCl3, Zn βHg / HCl (4) Br2 / AlBr3, CH3 COCl / AlCl3, HNO3 /H2 SO4, Zn / HCl
Q38. Consider the given reaction, percentage yield of : (1) C > A > B (2) B > C > A (3) A > C > B (4) C > B > A
Q44.The Crystal Field Stabilization Energy (CFSE) and magnetic moment (spin-only) of an octahedral aqua complex of a metal ion Mπ+ are -0 . 8Ξ0 and 3 . 87 BM, respectively. Identify Mπ+ : (1) V3 + (2) Co2 + (3) Cr3 + (4) Mn4 +
Q44.The correct order of intensity of colors of the compounds is: (1) [Ni(CN)4]2β> [NiCl4]2β> [Ni (H2O)6]2+ (2) [Ni (H2O)6]2+ > [NiCl4]2β> [Ni(CN)4]2β (3) [NiCl4]2β> [Ni (H2O)6]2+ > [Ni(CN)4]2β (4) [NiCl4]2β> [Ni(CN)4]2β> [Ni (H2O)6]2+ C2H5 OH β
Q45.Which one of the following complexes is violet in colour? (1) Fe4 [Fe(CN)6]3 β H2O (2) [Fe(CN)5 NOS]4β (3) [Fe(SCN)6]4β (4) [Fe(CN)6]4β
Q49.The correct sequential addition of reagents in the preparation of 3βnitrobenzoic acid from benzene is: JEE Main 2021 (26 Aug Shift 1) JEE Main Previous Year Paper (1) Br2 / AlBr3, HNO3 /H2 SO4, Mg / ether, CO2, H3O+ (2) Br2 / AlBr3, NaCN, H3O+, HNO3 /H2 SO4 (3) Br2 / AlBr3, HNO3 /H2 SO4, NaCN, H3O+ (4) HNO3 /H2 SO4, Br2 / AlBr3, Mg / ether, CO2, H3O+
Q61.The number of pairs π, π of real numbers, such that whenever πΌ is a root of the equation π₯2 + ππ₯+ π= 0, πΌ2 - 2 is also a root of this equation, is : (1) 6 (2) 8 (3) 4 (4) 2
Q61.The number of seven digit integers with sum of the digits equal to 10 and formed by using the digits 1, 2 and 3 only is: (1) 77 (2) 82 (3) 42 (4) 35
Q62.If π is very small as compared to the value of π, so that the cube and other higher powers of π can be neglected π in the identity 1 1 1 1 β¦ . + πΌπ+ π½π2 + πΎπ3 π- π+ π- 2π+ π- 3π+ π- ππ= then the value of πΎ is : (1) π2 + π (2) π+ π 3π3 3π2 (3) π2 (4) π+ π2 3π3 3π3
Q63. Let ππ= 1 Β· ( π- 1 ) + 2 Β· ( π- 2 ) + 3 Β· ( π- 3 ) + β¦ + ( π- 1 ) Β· 1, πβ©Ύ4 . β 2 Sn 1 The sum βn = 4 n! - ( n - 2 ) ! is equal to : π- 2 e - 1 (1) (2) 6 3 (3) e (4) e 6 3 20 1 4 = . If the sum of this π΄. π. is 189, then a6a16
Q63.If the greatest value of the term independent of x in the expansion of (x sin Ξ± + a cosx Ξ± )10 is (5!)210! value of a is equal to: (1) β1 (2) 1 (3) β2 (4) 2 10100 1
Q63.If 0 < a, b < 1 , and tanβ1 a + tanβ1 b = Ο4 , then the value of (a + b) β( a2+b22 ) ( a3+b33 ) β( a4+b44 ) is : (1) loge( 2e ) (2) e (3) e2 β1 (4) loge 2
Q64.Let [x] denote greatest integer less than or equal to x . If for n βN, (1 βx + x3) n = β3nj=0 ajxj , then [ 3n2 ] [ 3nβ12 ] β j=0 a2j + 4 β j=0 a2j+1 is equal to : (1) 2 (2) 2nβ1 (3) 1 (4) n
Q64.A circle C touches the line x = 2y at the point (2, 1) and intersects the circle C1 : x2 + y2 + 2y β5 = 0 at two points P and Q such that PQ is a diameter of C1 . Then the diameter of C is : (1) 4β15 (2) β285 (3) 15 (4) 7β5 = 1 having eccentricity β52 . If the tangent and
Q64.Let r1 and r2 be the radii of the largest and smallest circles, respectively, which pass through the point (β4, 1) and having their centres on the circumference of the circle x2 + y2 + 2x + 4y β4 = 0. If r1 = a + bβ2, then r2 a + b is equal to: (1) 3 (2) 11 (3) 5 (4) 7
Q64.If 0 < x, y < Ο and cos x + cos y βcos(x + y) = 23 , then sin x + cos y is equal to: (1) 1 (2) β3 2 2 (3) 1ββ3 (4) 1+β3 2 2 JEE Main 2021 (25 Feb Shift 2) JEE Main Previous Year Paper
Q64.Let the circle S : 36x2 + 36y2 β108x + 120y + C = 0 be such that it neither intersects nor touches the co- ordinate axes. If the point of intersection of the lines, x β2y = 4 and 2x βy = 5 lies inside the circle S, then: (1) 25 9 < C < 133 (2) 100 < C < 165 (3) 81 < C < 156 (4) 100 < C < 156 = 1, a > b. Let E2 be another ellipse such that it touches the end points of major axis of E1
Q65.Let an ellipse πΈ: π₯2 + π¦2 = 1, π2 > π2, passes through 3 1 and has eccentricity 1 If a circle, centered at β 2, β3. π2 π2 2 focus πΉ( πΌ, 0 ) , πΌ> 0, of πΈ and radius β3, intersects πΈ at two points π and π, then ππ2 is equal to : (1) 8 (2) 4 3 3 16 (3) (4) 3 3
Q65.The sum of solutions of the equation 1+sin x = |tan 2x|, x β(βΟ2 , Ο2 ) β{βΟ4 , Ο4 } is: (1) 10 Ο (2) β7Ο30 (3) βΟ15 (4) β11Ο30