List of top Questions asked in JEE Main, KCET

White light is incident on one of the refracting surfaces of a prism of angle $5^\circ$. If the refractive indices for red and blue colours are $1.641$ and $1.659$ respectively, the angular separation between these two colours when they emerge out of the prism is
The unit of Stefan's constant is
The mass of glucose that should be dissolved in $50\, g$ of water in order to produce the same lowering of vapour pressure as is produced by dissolving $1\, g$ of urea in the same quantity of water is
The decomposition of a certain mass of $CaCO_3$ gave $11.2\, dm^3$ of $CO_2$ gas at $STP$. The mass of $KOH$ required to completely neutralise the gas is
The brown ring test for nitrates depends on
Glucose contains in addition to aldehyde group
An example for autocatalysis is
If $a, b$ and $c \in N$ which one of the following is not true ?
Liquor ammonia bottles are opened only after cooling. This is because
Vector which is perpendicular to $ a\,\cos \,\theta \,\hat{i}+b\,\sin \,\theta \,\,\hat{j} $ is
The digit in the units place in the number $7^{289}$ is
The projection of the vector $2\hat{i}+\hat{j}-3\hat{k}$ on the vector $\hat{i}-2\hat{j}-\hat{k}$ is
A radioactive isotope has a half life of $10$ days. If today $125$ mg is left over, what was its original weight $40$ days earlier ?
In the lac-operon model, lactose molecules function as
In the group $ (Q^+ ,\star )$ of positive rational numbers w.r.t. the binary operation $\star$ defined by $a^{\star} b=\frac {ab}{3} , \forall a,b \in Q^{+}$ the solution of the equation $5 ^{\star} x=4^{-1}$ in $Q^+$ is
In the group $G. = \{1, 3,7,9 \}$ under multiplication modulo $10$, the inverse of $3$ is
The identity element in the group $M = \left\{ \begin{bmatrix} x & x \\ x & x\\ \end{bmatrix} | x \ \in \ R, x \neq 0 \right\}$ with respect to matrix multiplication is
Which of the following is called detritivore ?
The converse of the contrapositive of $p \to \sim q$ is
If $A=\begin{bmatrix} {3}&{5}\\ {2}&{0}\\ \end{bmatrix} $ and $B$ = $\begin{bmatrix} {1}&{17}\\ {0}&{-10}\\ \end{bmatrix} $then $|AB|$ is equal to
The solutions of the equation $\begin{vmatrix} {x}&{2} &{-1}\\ {2}&{5}& {x} \\ {-1}&{z}&{x}\\ \end{vmatrix} =0$ are
The inverse of the matrix $\begin{bmatrix} {5}&{-2}\\ {3}&{1}\\ \end{bmatrix}$ is is
The contrapositive of "If two triangles are identical, then these are similar" is
The reaction in which phenol differs from alcohol is:
A mixture of two moles of carbon monoxide and one mole of oxygen, in a closed vessel is ignited to convert the carbon monoxide to carbon dioxide.If $\Delta H$ is the enthalpy change and $\Delta E$ is the change in internal energy, then,