List of top Questions asked in JEE Main- 2021

With respect to drug-enzyme interaction, identify the wrong statement.
Which of the following reaction is an example of ammonolysis?
Which of the following is correct structure of tyrosine?
Mesityl oxide is a common name of :
Which of the following is an aromatic compound?
Given below are two statements :
Statement I : Potassium permanganate on heating at 573K forms potassium manganate.
Statement II : Both potassium permanganate and potassium manganate are tetrahedral and paramagnetic in nature.
In the light of the above statements, choose the most appropriate answer from the options given below :
Given below are two statements :

Statement I : Retardation factor (Rf) can be measured in meter/centimeter.

Statement II : Rf value of a compound remains constant in all solvents.

Choose the most appropriate answer from the options given below :
A central atom in a molecule has two lone pairs of electrons and forms three single bonds. The shape of this molecule is :

The above reaction requires which of the following reaction conditions?

The product "A" in the above reaction is :

Product "A" in the above chemical reaction is :
Which of the following compound CANNOT act as a Lewis base?
Hoffmann bromomide degradation of benzamide gives product A, which upon heating with \(\mathrm{CHCl_3}\) and NaOH gives product B.
The structures of A and B are :
If 2.5 \(\times\) 10\(^{-6}\) N average force is exerted by a light wave on a non-reflecting surface of 30 cm\(^2\) area during 40 minutes of time span, the energy flux of light just before it falls on the surface is ___________ W/cm\(^2\). (Round off to the Nearest Integer)
(Assume complete absorption and normal incidence conditions are there)
What is the spin-only magnetic moment value (BM) of a divalent metal ion with atomic number 25, in it's aqueous solution?
The absolute value of the electron gain enthalpy of halogens satisfies :
For VHF signal broadcasting, ___________ km\(^2\) of maximum service area will be covered by an antenna tower of height 30 m, if the receiving antenna is placed at ground. Let radius of the earth be 6400 km. (Round off to the Nearest Integer) (Take \(\pi\) as 3.14)
Two blocks (m = 0.5 kg and M = 4.5 kg) are arranged on a horizontal frictionless table as shown in figure. The coefficient of static friction between the two blocks is \(\frac{3}{7}\). Then the maximum horizontal force that can be applied on the larger block so that the blocks move together is ___________ N. (Round off to the Nearest Integer) [Take g as 9.8 ms\(^{-2}\)]
A parallel plate capacitor whose capacitance C is 14 pF is charged by a battery to a potential difference V = 12 V between its plates. The charging battery is now disconnected and a porcelin plate with k = 7 is inserted between the plates, then the plate would oscillate back and forth between the plates with a constant mechanical energy of _____________ pJ. (Assume no friction)
The following bodies,
(1) a ring
(2) a disc
(3) a solid cylinder
(4) a solid sphere,
of same mass 'm' and radius 'R' are allowed to roll down without slipping simultaneously from the top of the inclined plane. The body which will reach first at the bottom of the inclined plane is ___________. [Mark the body as per their respective numbering given in the question]
The equivalent resistance of series combination of two resistors is 's'. When they are connected in parallel, the equivalent resistance is 'p'. If s = np, then the minimum value for n is ____________. (Round off to the Nearest Integer)
Four identical rectangular plates with length, l = 2 cm and breadth, b = \(\frac{3}{2}\) cm are arranged as shown in figure. The equivalent capacitance between A and C is \(\frac{x\varepsilon_0}{d}\). The value of x is ______________. (Round off to the Nearest Integer)
The angular speed of truck wheel is increased from 900 rpm to 2460 rpm in 26 seconds. The number of revolutions by the truck engine during this time is _____________. (Assuming the acceleration to be uniform).
The radius in kilometer to which the present radius of earth (R = 6400 km) to be compressed so that the escape velocity is increased 10 times is ___________.
An electron of mass m and a photon have same energy E. The ratio of wavelength of electron to that of photon is : (c being the velocity of light)