List of top Questions asked in JEE Main

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): NH$_3$ and NF$_3$ molecule have pyramidal shape with a lone pair of electrons on nitrogen atom. The resultant dipole moment of NH$_3$ is greater than that of NF$_3$.
Reason (R): In NH$_3$, the orbital dipole due to lone pair is in the same direction as the resultant dipole moment of the N$-$H bonds. F is the most electronegative element.
In the light of the above statements, choose the correct answer from the options given below:

The correct nomenclature for the following compound is:

Identify the major product in the following reaction.

While preparing crystals of Mohr's salt, dil. \(H_2SO_4\) is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil. \(H_2SO_4\) is added here to:

Match List - I with List - II.

List - I	List - II
(A) ICl	(IV) Linear
(B) ICl3	(I) T-Shape
(C) ClF5	(II) Square pyramidal
(D) IF7	(III) Pentagonal bipyramidal

Choose the correct answer from the options given below:

The current in an inductor is given by I = (3t + 8) where t is in second. The magnitude of induced emf produced in the inductor is 12 mV. The self inductance of the inductor _______ mH.

A wire of resistance 20 \(\Omega\) is divided into 10 equal parts. A combination of two parts are connected in parallel and so on. Now resulting pairs of parallel combination are connected in series. The equivalent resistance of final combination is _______ \(\Omega\).

The maximum height reached by a projectile is 64 m. If the initial velocity is halved, the new maximum height of the projectile is ______ m.

The electric field at point p due to an electric dipole is E. The electric field at point R on equitorial line will be\(\frac{E}{x}\). The value of x :

A hollow sphere is rolling on a plane surface about its axis of symmetry. The ratio of rotational kinetic energy to its total kinetic energy is \(\frac{x}{5}\). The value of x is ________.

A sonometer wire of resonating length 90 cm has a fundamental frequency of 400 Hz when kept under some tension. The resonating length of the wire with fundamental frequency of 600 Hz under same tension _______ cm.

In a single slit experiment, a parallel beam of green light of wavelength 550 nm passes through a slit of width 0.20 mm. The transmitted light is collected on a screen 100 cm away. The distance of first order minima from the central maximum will be\(x \times 10^{–5}\)m. The value of x is :

The shortest wavelength of the spectral lines in the Lyman series of hydrogen spectrum is 915 Å. The longest wavelength of spectral lines in the Balmer series will be _______ Å.

A solenoid of length 0.5 m has a radius of 1 cm and is made up of 'm' number of turns. It carries a current of 5 A. If the magnitude of the magnetic field inside the solenoid is $6.28 \times 10^{-3}$ T, then the value of m is:

The ratio of heat dissipated per second through the resistance 5 ohm and 10 ohm in the circuit given below is :

A satellite revolving around a planet in stationary orbit has time period 6 hours. The mass of planet is one-fourth the mass of earth. The radius orbit of planet is: (Given = Radius of geostationary orbit for earth is $4.2 \times 10^4$ km

A heavy box of mass 50 kg is moving on a horizontal surface. If co-efficient of kinetic friction between the box and horizontal surface is 0.3 then force of kinetic friction is :

A vernier callipers has 20 divisions on the vernier scale, which coincides with 19^th division on the main scale. The least count of the instrument is 0.1 mm. One main scale division is equal to ____mm.

Match List-I with List-II :

List-I	List-II
(A) A force that restores an elastic body of unit area to its original state	(I) Bulk modulus
(B) Two equal and opposite forces parallel to opposite faces	(IV) Shear modulus
(C) Forces perpendicular everywhere to the surface per unit area same everywhere	(III) Stress
(D) Two equal and opposite forces perpendicular to opposite faces	(II) Young's modulus

Choose the correct answer from the options given below :

During an adiabatic process, if the pressure of a gas is found to be proportional to the cube of its absolute temperature, then the ratio of \(\frac{C_p}{C_v}\) for the gas is : 

Match List-I with List-II :-

List-I EM-Wave	List-II Wavelength Range
(A) Infra-red	(III) 1 mm to 700 nm
(B) Ultraviolet	(II) 400 nm to 1 nm
(C) X-rays	(IV) 1 nm to \(10^{-3}\) nm
(D) Gamma rays	(I) \(<10^{-3}\) nm

Choose the correct answer from the options given below :

A body is moving unidirectionally under the influence of a constant power source. Its displacement in time t is proportional to :

The output (Y) of logic circuit given below is 0 only when :

What is the dimensional formula of \( ab^{-1} \) in the equation \[ \left( P + \frac{a}{V^2} \right) (V - b) = RT, \] where letters have their usual meaning.

A series LCR circuit is subjected to an AC signal of 200 V, 50 Hz. If the voltage across the inductor (L = 10 mH) is 31.4 V, then the current in this circuit is ________ :