List of top Questions asked in WBJEE

An integrating factor of the differential equation $x\frac{dy}{dx}+y\log x=x{e}^x{x}^{-\frac{1}{2}\log x},(x>0)$

ABCD is a parallelogram. If $P$ and $Q$ are the respective midpoints of$\overrightarrow{\mathrm{BC}}$ and $\overrightarrow{\mathrm{AD}},$ then $,\overrightarrow{\mathrm{AB}}+\overrightarrow{\mathrm{DC}}$ is equal to

A galvanometer has 40 divisions and a sensitivity of 12 μA/div. it can be converted into a voltmeter to read 3 V by connecting-

0.066 g of a metal was deposited when a current of 2 ampere passed for 100 seconds through an aqueous solution of its metal ion. The equivalent mass of the metal is-

The following reaction is an example of

The value of $\sec [{\tan }^{-1}\left(\frac{b+a}{b-a}\right)-{\tan }^{-1}\left(\frac{a}{b}\right)]$

The minimum value of $f(x)={\sin }^{4}x+{\cos }^{4}x,0\le x\le \frac{\pi }{2}$

The probability that in a family of 5 members, exactly 2 members have birthdays on Sunday, is

If A1, A2; G1, G2; and H1, H2 are two AMs, GMs and HMs between two quantities, then the value of $\frac{G_1{G}_2}{H_1{H}_2}$ is

If $\overrightarrow{A}=\hat{i}+2\overrightarrow{j}+3\hat{k},\overrightarrow{B}=-\hat{i}+2\hat{j}+\hat{k},\overrightarrow{C}=3\hat{i}+j$ and $\overrightarrow{A}+1\overrightarrow{B}$ is perpendicular to $\overrightarrow{\mathrm{C}},$ thent is equal to

The energy of electron in 1st orbit of Hydrogen atom is –2.18 × 10^-18 Joule. The third ionisation energy of Li⁺² ion is

In $P{O}_4^{3-}$the formal charge on each oxygen atom and P − O bond order respectively are

If a particle moves in such a way that the displacement is proportional to the square of the velocity acquired, then its acceleration is

An electron jumps from the fourth orbit to the second orbit of hydrogen atom. If Rydberg’s constant R is equal to 10⁷ m^–1, then the frequency of the emitted radiation in Hz will be

Consider the reaction 2A + B →products, when the concentration of A alone was doubled, the half-life of the reaction did not change. When the concentration of B alone was doubled, the rate was not altered. The unit of rate constant for this reaction is

Which of the following type of compound is used to increase the hardness of the silicone polymer.

The curve represented by the equation 4x² + 16y² - 24x - 32y - 12 = 0 is

The derivative of${\tan }^{-1}\left(\frac{\sqrt{1+x^2}-1}{x}\right)$ with respect to ${\tan }^{-1}\left(\frac{2x\sqrt{1-x^2}}{1-2x^2}\right)$ at $x=0$

The actinoids exhibit more number of oxidation states in general than the lanthanoids because

The solubility product of silver chloride is 1.8 × 10^-10 at 298 k. The solubility of AgCl in 0.01 M KCl aqueous solution in mol dm^-3 is

Among the following complex compounds–${\mathrm{K}}_3[\mathrm{Fe}(\mathrm{CN}{)}_6]$$(i)$$\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_6\right]{\mathrm{Cl}}_3$(ii) ${\mathrm{K}}_2[\mathrm{Pt}(\mathrm{CN}{)}_4]$$(\mathrm{iii})$$\left[\mathrm{Zn}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]{\left({\mathrm{NO}}_3\right)}_2$$(iv)$diamagnetic complexes are –

products can be

A coin is tossed again and again. If tail appears on first three tosses, then the chance that head appears on fourth toss is

If α and β are the roots of the equation x² + x + 1 = 0, then the equation whose roots are α¹⁹ and β⁷ is