List of top Questions asked in JEE Main- 2019

The pair that has similar atomic radii is :

The peptide that gives positive ceric ammonium nitrate and carbylamine tests is :

The plane through the intersection of the planes $x + y + z = 1$ and $2x + 3y - z + 4 = 0$ and parallel to y-axis also passes through the point :

The plane which bisects the line segment joining the points (-3,-3,4) and (3,7,6) at right angles, passes through which one of the following points ?

The primary pollutant that leads to photochemical smog is :

The principle of column chromatography is :

The structure of Nylon-6 is :

The structures of beryllium chloride in the solid state and vapour, phase, respectively,are :

The sum $1+ \frac{1^{3} +2^{3}}{1+2} + \frac{1^{3}+2^{3}+3^{3}}{1+2+3} +.... + \frac{1^{3} +2^{3}+3^{3} +....+15^{3}}{1+2+3+...+15} - \frac{1}{2} \left(1+2+3+...+15\right)$

The value of cos $^2 10^{\circ} - cos10^{\circ} cos50^{\circ} + cos^2 50^{\circ}$

The value of $\cos \frac{\pi}{2^{2}} .\cos \frac{\pi}{2^{3} } . ...... .\cos \frac{\pi}{2^{10}} .\sin \frac{\pi}{2^{10}} $ is :

The variation of refractive index of a crown glass thin prism with wavelength of the incident light is shown. Which of the following graphs is the correct one, if $D_m$ is the angle of minimum deviation?

The volume strength of $1 \,M H _{2} O _{2}$ is (Molar mass of $\left. H _{2} O _{2}=34 \,g\, mol ^{-1}\right)$

There are two long co-axial solenoids of same length $l$. the inner and outer coils have radii $r_1$ and $r_2$ and number of turns per unit length $n_1$ and $n_2$ respectively. The rate of mutual inductance to the self-inductance of the inner-coil is :

Three blocks $A, B$ and $C$ are lying on a smooth horizontal surface, as shown in the figure. $A$ and $B$ have equal masses, $m$ while $C$ has mass $M$. Block $A$ is given an brutal speed $v$ towards $B$ due to which it collides with $B$ perfectly inelastically. The combined mass collides with $C$, also perfectly inelastically $\frac{5}{6}$ th of the initial kinetic energy is lost in whole process. What is value of $M/m$ ?

Three Carnot engines operate in series between a heat source at a temperature $T_1$ and a heat sink at temperature $T_4$ (see figure). There are two other reservoirs at temperature $T_2$, and $T_3$, as shown, with $T_2 > T_2 > T_3 > T_4$ . The three engines are equally efficient if:

Three particles of masses $50\, g, 100\, g$ and $150\, g$ are placed at the vertices of an equilateral triangle of side $1\, m$ (as shown in the figure). The $(x, y)$ coordinates of the centre of mass will be :

Two blocks $A$ and $B$ of masses $m_A = 1 \; kg$ and $m_B = 3 \; kg$ are kept on the table as shown in figure. The coefficient of friction between $A$ and $B$ is $0.2$ and between $B$ and the surface of the table is also $0.2.$ The maximum force $F$ that can be applied on $B$ horizontally, so that the block $A$ does not slide over the block $B$ is : (Take $g = 10 \; m/s^2$)

Two coherent sources produce waves of different intensities which interfere. After interference, the ratio of the maximum intensity to the minimum intensity is $16$. The intensity of the waves are in the ratio:

Two equal resistance when connected in series to a battery, consume electric power of $60\, W$. If these resistances are now connected in parallel combination to the same battery, the electric power consumed will be :

Two guns $A$ and $B$ can fire bullets at speeds $1\, km/s$ and $2\, km/s$ respectively. From a point on a horizontal ground, they are fired in all possible directions. The ratio of maximum areas covered by the bullets fired by the two guns, on the ground is :

Two integers are selected at random from the set {1, 2,...., 11}. Given that the sum of selected numbers is even, the conditional probability that both the numbers are even is :

Two plane mirrors arc inclined to each other such that a ray of light incident on the first mirror $(M_1)$ and parallel to the second mirror $(M_2)$ is finally reflected from the second mirror $(M_2)$ parallel to the first mirror $(M_1)$. The angle between the two mirrors will be :

Two solids dissociate as follows $ {A(s) <=> B(g) + C(g) ; K_{p_1} = x \; atm^2}$ $ {D(s) <=> C(g) + E(g) ; K_{p_2} = y \; atm^2}$ The total pressure when both the solids dissociate simultaneously is :

A solution containing $62\, g$ ethylene glycol in $250 \,g$ water is cooled to $-10^{\circ}C$. If $K_f$ for water is $1.86\, K\, kg \,mol^{-1}$, the amount of water (in g) separated as ice is :