List of top Questions asked in WBJEE

If fourth term of an A.P. is zero, then $\frac{t_{25}}{t_{11}}$ is, where $t_n$ denotes the $n^{\text{th }}$ term of AP.

If in a triangle ABC, sin A, sin B, sin C are in A.P., then 

$\int \frac{a^{x/2}}{\sqrt{a^{-x}-a^x}}\mathrm{dx}$ is equal to

The shortest distance from the point (1, 2, -1) to the surface of the sphere x² + y² + z² = 54 is

If a point P is equidistant from A(1, 3), B(-3, 5) and C(5, -1), then PA is equal to

If $\sin \theta =\frac{2t}{1+t^2}$ and $\theta$ lies in the second quadrant, then $\cos \theta$ is equal to

Evaluate the integral: ${\int }_1^2\log xdx$

Consider the following species $(\mathrm{I}){\mathrm{S}}_4{\mathrm{O}}_6^{2-}$$(\mathrm{II}){\mathrm{S}}_3{\mathrm{O}}_9$$(\mathrm{III}){\mathrm{S}}_2{\mathrm{O}}_5^{2-}$$(\mathrm{IV}){\mathrm{P}}_3{\mathrm{O}}_9^{3-}$Which of the above species have same number of $X-0-X$ linkages? $(X=P\text{ or }S)$

Q in the above sequence of reactions is

The correct statement(s) about following sugars (X) and (Y) is/are:

Which one of the following observations is not true when a mixture of KCl, K2Cr2O7 and conc. H2SO4 is warmed carefully?

The addition of HBr to 2-pentene gives

Blackened oil painting can be restored into original form by the action of:

Consider the following diagram and mark the correct answer.

Directions: The following question has four choices, out of which one or more are correct.When photons of energy 4.25 eV strike the surface of a metal $A$, the ejected photoelectrons have minimum kinetic energy $T_A$ expressed in eV and de Broglie wavelength ${\lambda }_A.$ The maximum kinetic energy ofphotoelectrons liberated from another metal $B$ by photons of energy 4.70 eV is $T_B=(T_A-1.50eV)$. If the de Broglie wavelength of these photoelectrons is ${\lambda }_B=2{\lambda }_A$, then

If $A=\left(\begin{array}{cc}3& x-1\\ 2x+3& x+2\end{array}\right)$ is a symmetric matrix, then the value of $x$ is

If $\omega (\ne 1)$ is a cube root of unity and ${(1+{\omega }^2)}^n={(1+{\omega }^4)}^n,$ then the leastpositive value of $n$ is

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

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-

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

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

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

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