List of top Questions asked in JEE Main

The area of the region : R = {(x, y) : 5x² ≤ y ≤ 2x² + 9} is :
If the variance of 10 natural numbers 1, 1, 1, ......., 1, k is less than 10, then the maximum possible value of k is ______
Let f(x) = -55x (x<-5), 2x³ - 3x² - 120x (-5 ≤ x ≤ 4), 2x³ - 3x² - 36x - 336 (x>4). Let A = {x ∈ ℝ : f is increasing}. Then A is equal to :
The angle of elevation of a jet plane from a point A on the ground is 60°. After 20 s at speed 432 km/h, the angle changes to 30°. If the jet plane is at constant height, then its height is :
The value of the integral, ∫ from 1 to 3 of [x² - 2x - 2] dx, where [x] denotes the greatest integer less than or equal to x, is :
The negation of the statement ~p ∧ (p ∨ q) is :
Let A and B be 3 × 3 real matrices such that A is symmetric matrix and B is skew-symmetric matrix. Then the system of linear equations (A²B² - B²A²) X = O, where X is a 3 × 1 column matrix of unknown variables and O is a 3 × 1 null matrix, has :
Let f(x) be a differentiable function defined on [0, 2] such that f'(x) = f'(2-x) for all x ∈ (0, 2), f(0) = 1 and f(2) = e². Then the value of ∫ from 0 to 2 f(x) dx is :
If the curve y = ax² + bx + c passes through (1, 2) and the tangent at origin is y = x, then a, b, c are :
Let a, b ∈ R. If the mirror image of the point P(a, 6, 9) with respect to the line (x-3)/7 = (y-2)/5 = (z-1)/(-9) is (20, b, -a - 9), then |a + b| is equal to :
If P is a point on the parabola y = x² + 4 which is closest to the straight line y = 4x - 1, then the co-ordinates of P are :
In polymer Buna-S : 'S' stands for :
Match List - I and List - II. List - I: (a) Valium, (b) Morphine, (c) Norethindrone, (d) Vitamin B12 List - II: (i) Antifertility drug, (ii) Pernicious anaemia, (iii) Analgesic, (iv) Tranquilizer
The formula of a gaseous hydrocarbon which requires 6 times of its own volume of O2 for complete oxidation and produces 4 times its own volume of CO2 is CxHy. The value of y is _________
The incorrect statement among the following is :
What is the correct order of the following elements with respect to their density ?
Given below are two statements : Statement I : The value of the parameter “Biochemical Oxygen Demand (BOD)” is important for survival of aquatic life. Statement II : The optimum value of BOD is 6.5 ppm. In the light of the above statements, choose the most appropriate answer from the options given below :
Most suitable salt which can be used for efficient clotting of blood will be :
Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere. Reason R : Hydrogen is the lightest element.
According to Bohr's atomic theory : (A) Kinetic energy of electron is $\propto Z^2 / n^2$. (B) The product of velocity (v) of electron and principal quantum number (n), 'vn' $\propto Z^2$. (C) Frequency of revolution of electron in an orbit is $\propto Z^2 / n^3$. (D) Coulombic force of attraction on the electron is $\propto Z^3 / n^4$. Choose the most appropriate answer :
A uniform metallic wire is elongated by 0.04 m when subjected to a linear force F. The elongation, if its length and diameter is doubled and subjected to the same force will be ________ cm.
A uniform thin bar of mass 6 kg and length 2.4 meter is bent to make an equilateral hexagon. The moment of inertia about an axis passing through the centre of mass and perpendicular to the plane of hexagon is __________ x 10\^{-1} kg m².
An X-ray tube is operated at 1.24 million volt. The shortest wavelength of the produced photon will be :
The de Broglie wavelength of a proton and α-particle are equal. The ratio of their velocities is :
According to Bohr atom model, in which of the following transitions will the frequency be maximum ?