List of top Questions asked in JEE Main

The average mass of rain drops is $3.0 \times 10^{-5}$ kg and their average terminal velocity is $9\, m/s.$ Calculate the energy transferred by rain to each square metre of the surface at a place which receives $100\, cm$ of rain in a year.

The integral $\int x \,cos^{-1}\left(\frac{1-x^{2}}{1+x^{2}}\right) \,dx\, \left(x > 0\right)$ is equal to :

A cone of base radius R and height h is located in a uniform electric field $\overrightarrow{E}$ parallel to its base. The electric flux entering the cone is :

Which series of reactions correctly represents chemical relations related to iron and its compound?

A capillary tube is immersed vertically in water and the height of the water column is $x$. When this arrangement is taken into a mine of depth $d$, the height of the water column is $y$. If $R$ is the radius of earth, the ratio $\frac{x}{y} $ is :

Similarity in chemical properties of the atoms of elements in a group of the Periodic table is most closely related to :

Among the following oxoacids, the correct decreasing order of acidic strength is

Which of the following statements about $Na_2O_2$ is not correct?

For sky wave propagation, the radio waves must have a frequency range in between :

For the reaction, 3A + 2B $\to$ C + D, the differential rate law can be written as :

On heating water, bubbles being formed at the bottom of the vessel detatch and rise. Take the bubbles to be spheres of radius $R$ and making a circular contact of radius r with the bottom of the vessel. If $r << R$, and the surface tension of water is T, value of r just before bubbles detatch is (density of water is $\rho_{w}$ )

The angular frequency of the damped oscillator is given by, $\omega = \sqrt{\left(\frac{k}{m} - \frac{r^{2}}{4m^{2}}\right)}$ where $k$ is the spring constant, $m$ is the mass of the oscillator and $r$ is the damping constant. If the ratio $\frac{r^{2}}{mk}$ is $8\%$, the change in time period compared to the undamped oscillator is approximately as follows :

The metal that cannot be obtained by electrolysis of an aqueous solution of its salts is

The correct order of bond dissociation energy among $N_2, O_2, O_2^-$ is shown in which of the following arrangements ?

Steel ruptures when a shear of $ 3.5 \times 10^8 \,Nm^{-2}$ is applied. The force needed to punch a $1\, cm$ diameter hole in a steel sheet $0.3\, cm$ thick is nearly :

From the following combinations of physical constants (expressed through their usual symbols) the only combination, that would have the same value in different systems of units, is :

An air bubble of radius $0.1\, cm$ is in a liquid having surface tension $0.06\, N/m$ and density $10^3\, kg/m^3$. The pressure inside the bubble is 1100 $Nm^{-2}$ greater than the atmospheric pressure. At what depth is the bubble below the surface of the liquid ? $(g = 9.8 \,ms^{-2})$

The gap between the plates of a parallel plate capacitor of area A and distance between plates $d$, is filled with a dielectric whose permittivity varies linearly from $\epsilon_{1}$ at one plate to $\epsilon_{2}$ at the other. The capacitance of capacitor is :

A bob of mass m attached to an inextensible string of length l is suspended from a vertical support. The bob rotates in a horizontal circle with an angular speed $\omega \,rad/s$ about the vertical support. About the point of suspension

For the reaction, $ SO_2 ( g) + \frac{1}{2} O_2 \, ( g) \rightleftharpoons SO_3 \, ( g) $ if $ K_P = K_C \, ( RT)^x $ X where, the symbols have usual meaning, then the value of x is (assuming ideality)

Three rods of copper , brass and steel are welded together to form a Y-shaped structure .Area of cross -section of each rod is $4cm^2$.End of copper rod is maintained at $100^{\circ}C$ whereas ends of brass and steel are kept at $0^{\circ C}$ Lengths of the copper, brass and steel rods are 46,13 and 12 cm respectively The rods are thermally insulated from surroundings except at ends.Thermal conductivities of copper , brass and steel are 092 , 0.26 and 0.12 in CGS units , respectively .Rate of heat flow throught cooper rod is

There is a circular tube in a vertical plane. Two liquids which do not mix and of densities $d_1$ and $d_2$ are filled in the tube. Each liquid subtends $90^\circ$ angle at centre. Radius joining their interface makes an angle a with vertical. Ratio $\frac{d_{1}}{d_{2}}$ is :

The octahedral complex of a metal ion $M^{3+} $ with four monodentate ligands $L_1,L_2,L_3 \, and \, L_4 $ absorb wavelengths in the region of red, green, yellow and blue, respectively. The increasing order of ligand strength of the four ligands is

In a monoclinic unit cell, the relation of sides and angles are respectively :

Which of the following series correctly represents relations between the elements from X to Y?
\(X\to Y\)