List of top Questions asked in JEE Main, KCET

The following statements are the steps in the catalytic action of an enzyme. Arrange them in correct sequence.
a) The active site of the enzyme, now in close proximity of the substrate, breaks the chemical bonds of the substrate and the new enzyme product complex is formed.
b) The substrate binds tightly to the enzyme, inducing a change in the active site of the enzyme.
c) The enzyme releases the products of the reaction and the free enzyme is ready to bind to another molecule of the substrate.
d) The substrate binds to the active site of the enzyme.
Consider an A.P. $a_1,a_2,\ldots,a_n$ with $a_1>0$, $a_2-a_1=-\dfrac{3}{4}$ and $a_n=\dfrac{a_1}{4}$. If \[ \sum_{i=1}^{n} a_i=\frac{525}{2}, \] then find $\sum_{i=1}^{17} a_i$.

The question figure shows the 3D view of the object. Choose the correct 2D view (Elevation) of the object looking in the direction of the arrow 


For a 1st order change R \(\rightarrow\) P, the concentration of Reactant R changes from 0.1 M to 0.025 M in 40 minutes. The rate of reaction when the concentration of R is 0.01 M is
A solid sphere of mass $5$ kg and radius $10$ cm is kept in contact with another solid sphere of mass $10$ kg and radius $20$ cm. The moment of inertia of this pair of spheres about the tangent passing through the point of contact is ___________ kg$\cdot$m$^2$.

Water flows through a horizontal tube as shown in the figure. The difference in height between the water columns in vertical tubes is 5 cm and the area of cross-sections at A and B are 6 cm\(^2\) and 3 cm\(^2\) respectively. The rate of flow will be ______ cm\(^3\)/s. (take g = 10 m/s\(^2\)).

Consider the following statements for [Ni(dmg)$_2$]: (A) It is a red coloured compound.
(B) It is readily soluble in water at pH = 9.
(C) Central metal ion has two unpaired electrons.
(D) It has four, 5-membered metal containing rings.

Match the list-I with list-II 

The relative lowering of vapour pressure produced by dissolving 18 g of urea (Molar mass = 60 g mol\(^{-1}\)) in 100 g of water is
Consider three point charges \(-2Q, Q\) and \(-Q\) and three surfaces S\(_1\), S\(_2\) and S\(_3\) as shown in the figure. Match the entries of List-I with that of List-II.
List-I
(a) Net flux through S\(_1\)
(b) Net flux through S\(_2\)
(c) Net flux through S\(_3\)
List-II
(i) \(\frac{-2Q}{\epsilon_0}\)
(ii) \(\frac{-Q}{\epsilon_0}\)
(iii) Zero
Codes:
An electron falls through a distance 1.5 cm in a uniform electric field of magnitude 2.0 \(\times\) 10\(^4\) N/C from rest. The time taken to cover this distance in second is \textunderscore\textunderscore\textunderscore\textunderscore\textunderscore.
(e = 1.6 \(\times\) 10\(^{-19}\) C, m\(_e\) = 9.11 \(\times\) 10\(^{-31}\) kg)
1 mole of He and 1 mole A are taken in a 10 L rigid container at 400 K, and equilibrium \( A \rightleftharpoons B \) is established. Calculate the partial pressure of He and B at equilibrium if \( K_c = 4 \).
In a DNA molecule, cytosine is 28%. Calculate the percentage of adenine.
The compound from which chlorobenzene cannot be prepared easily is
The line $L_{1}$ joining the two points $(-1, 2)$ and $(3, 6)$ divides the line $L_{2}$ which passes through $(3, -1)$ in the ratio $1 : 3$ internally, then the equation of $L_{2}$ is

If A = \(\{a, b, c, d, e, f\},\) then the number of subsets of A which contains at least 2 elements is 
 

The number of critical points of the function} \[ f(x)= \begin{cases} \dfrac{|\sin x|}{x}, & x\neq0\\ 1, & x=0 \end{cases} \] in the interval \((-2\pi,2\pi)\) is equal to:
A point charge is placed in a moving train. A passenger A sitting in the train and person B on the ground observe the fields due to this charge. Then
If the coefficient of \( x \) in the expansion of \[ (ax^2 + bx + c)(1 - 2x)^{26} \] is \(-56\) and the coefficients of \( x^2 \) and \( x^3 \) are both zero, then \( a + b + c \) is equal to
In a microscope of tube length $10\,\text{cm}$ two convex lenses are arranged with focal lengths $2\,\text{cm}$ and $5\,\text{cm}$. Total magnification obtained with this system for normal adjustment is $(5)^k$. The value of $k$ is ___.
A wafer of pure germanium crystal has two parts X and Y. The end X is obtained by doping with arsenic and Y with indium. It is connected to a battery as shown in the figure. Which of the following statements is correct?
The radius of first orbit in hydrogen atom is 5.3 \(\times\) 10\(^{-11}\) m. The kinetic energy E\(_K\), potential energy E\(_P\) and total energy E\(_T\) of electron in first orbit are
A small town with a demand of 900 kW of electric power at 220 V is situated 20 km away from an electric power generating station. The two-wires line has resistance per unit length of \( 5 \times 10^{-4} \ \Omega \text{m}^{-1} \). The town gets power from the line through 45000 V to 220 V stepdown transformer at a substation in the town. The line power loss in the form of heat is
If \[ \lim_{x\to 0} \frac{e^{(a-1)x}+2\cos bx+(c-2)e^{-x}} {x\cos x-\log_e(1+x)} =2, \] then \(a^2+b^2+c^2\) is equal to
The dimensional formula of \( \frac{1}{2}\varepsilon_0 E^2 \) (\(\varepsilon_0\) = permittivity of vacuum and \(E\) = electric field) is \(M^aL^bT^c\). The value of \(2a-b+c\) is: