List of top Questions asked in JEE Main- 2023

A current of $15 \,mA$ flows in the circuit asshown in figure The value of potentialdifference between the points $A$ and $B$ will be
The length of a seconds pendulum at a height h=2R from earth surface will be :
(Given : R= Radius of earth and acceleration due to gravity at the surface of earth g=π2ms−2)
Sound travels in a mixture of two moles of helium and $n$ moles of hydrogen If rms speed of gas molecules in the mixture is $\sqrt{2}$ times the speed of sound, then the value of $n$ will be
Let $\eta_1$ is the efficiency of an engine at $T _1=447^{\circ} C$ and $T _2=147^{\circ} C$ while $\eta_2$ is the efficiency at $T _1=947^{\circ} C$ and $T _2=47^{\circ} C$ The ratio $\frac{\eta_1}{\eta_2}$ will be :
An object is taken to a height above the surface of earth at a distance $\frac{5}{4} R$ from the centre of the earth Where radius of earth, $R =6400 km$ The percentage decrease in the weight of the object will be
A bag of sand of mass $98\, kg$ is suspended by a rope A bullet of $200\, g$ travelling with speed $10\, ms ^{-1}$ gets embedded in it, then loss of kinetic energy will be
A ball is projected from the ground with a speed $15\, ms ^{-1}$ at an angle $\theta$ with horizontal so that its range and maximum height are equal, then'tan $\theta$ ' will be equal to
Hydrogen atom from excited state comes to the ground by emitting a photon of wavelength $\lambda$ The value of principal quantum number 'n' of the excited state will be :(R : Rydberg constant)

Match List I with List II :
 

List-I (molecule)List-II (hybridization; shape)
AXeO3​isp3d ; linear
BXeF2​iisp3; pyramidal
CXeOF4​iiisp3d3; distorted octahedral
DXeF6​ivsp3d2 ;square pyramidal


Choose the correct answer from the options given below:

Two solutions $A$ and $B$ are prepared by dissolving $1 g$ of non-volatile solutes $X$ and $Y$ respectively in $1 \,kg$ of water The ratio of depression in freezing points for $A$ and $B$ is found to be $1: 4$ The ratio of molar masses of $X$ and $Y$ is :
$Ka _1, Ka _2$ and $Ka _3$ are the respective ionization constants for the following reactions (a), (b) and (c)
(a) $H _2 C _2 O _4 \rightleftharpoons H ^{+}+ HC _2 O _4^{-}$
(b) $HC _2 O _4^{-} \rightleftharpoons H ^{+}+ HC _2 O _4^{2-}$
(c) $H _2 C _2 O _4 \rightleftharpoons 2 H ^{+}+ C _2 O _4^{2-}$
The relationship between $K _{ a _1}, K _{ a _2}$ and $K _{ a _3}$ is given as
The molar conductivity of a conductivity cell filled with $10$ moles of $20\, mL\, NaCl$ solution is $\Lambda_{ m 1}$ and that of $20$ moles another identical cell heaving $80 \, mL \, NaCl$ solution is $\Lambda_{ m 2}$, The conductivities exhibited by these two cells are same The relationship between $\Lambda_{ m 2}$ and $\Lambda_{ m 1}$ is
The first ionization enthalpies of $Be , B , N$ and $O$ follow the order
High purity $(>9995 \%)$ dihydrogen is obtained by
The correct order of density is
The industrial activity held least responsible for global warming is :

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$

Assertion (A) : The beam of electrons show wave nature and exhibit interference and diffraction 

Reason (R) : Davisson Germer Experimentally verified the wave nature of electrons

In the light of the above statements, choose the most appropriate answer from the options given below :

100 balls each of mass $m$ moving with speed $v$ simultaneously strike a wall normally and reflected back with same speed, in time $t s$ The total force exerted by the balls on the wall is

The correct relation between $\gamma=\frac{ c _{ p }}{ c _{ v }}$ and temperature $T$ is :

$Nd ^{2+}=$ ___________

The radius of electron's second stationary orbit in Bohr's atom is $R$ The radius of 3rd orbit will be

If the two metals $A$ and $B$ are exposed to radiation of wavelength $350 mm$. The work functions of metals $A$ and $B$ are $4.8 eV$ and $2.2 eV$. Then choose the correct option

A hypothetical gas expands adiabatically such that its volume changes from 08 litres to 27 litres. If the ratio of final pressure of the gas to initial pressure of the gas is $\frac{16}{B 1}$. Then the ratio of $\frac{C p}{C v}$ will be

Let $P$ be the plane, passing through the point $(1,-1,-5)$ and perpendicular to the line joining the points $(4,1,-3)$ and $(2,4,3)$. Then the distance of $P$ from the point $(3,-2,2)$ is

Benzyl isocyanide can be obtained by:
Benzyl Isocynide
Choose the correct answer from the options given below: