List of top Questions asked in JEE Main- 2023

A block of mass 100 gm is placed on a smooth surface, moves with acceleration of a=2x, then the change in kinetic energy can be given as \(\left(\frac{x^n}{10}\right)\). Find the value of n.

A car is moving with a speed of 15 m/s towards a stationary wall. A person in the car pressed the horn and experienced the change in frequency of 40 Hz due to reflection from the stationary wall. Find the frequency of the horn.
(Use \(𝑣_{sound}\) = 330 m/s)

If the length of a conductor is increased by 20% and cross-sectional area is decreased by 4% ,then calculate the percentage change in the resistance of the conductor.

Eight copper wire of length $l$ and diameter $d$ are joined in parallel to form a single composite conductor of resistance $R$ If a single copper wire of length $2 l$ have the same resistance $(R)$ then its diameter will be ______$d$

The energy band gap of semiconducting material to produce violet (wavelength = $4000 \mathring{A}$ ) LED is ______$eV$ (Round off to the nearest integer)

The required height of a TV tower which can cover the population of $603$ lakh is $h$ If the average population density is $100$ per square $km$ and the radius of earth is $6400\, km$, then the value of $h$ will be ______$m$

$SO _2 Cl _2$ on reaction with excess of water results into acidic mixture $SO _2 Cl _2+2 H _2 O \rightarrow H _2 SO _4+2 HCl$ 16 moles of $NaOH$ is required for the complete neutralisation of the resultant acidic mixture The number of moles of $SO _2 Cl _2$ used is :

Choose the correct option. 

Most stable product of the following reaction is:

A compound A on reaction with X and Y produces the same major product but different by product a and b Oxidation of  a gives a substance produced by ants X and Y respectively are :

The geometry around boron in the product 'B' formed from the following reaction is $ BF _3+ NaH \xrightarrow{450 K } A + NaF$ $ A + NMe _3 \rightarrow B$

The IUPAC nomenclature of an element with electronic configuration $[ Rn ] 5 f ^{14} 6 d ^1 7 s ^2$ is :

$20 \,mL$ of $01 \,M \,NH _4 OH$ is mixed with $40\, mL$ of $005\, M \,HCl$ The $pH$ of the mixture is nearest to: (Given: $K _{ b }\left( NH _4 OH \right)=1 \times 10^{-5}, \log 2=030$, $\log 3=048, \log 5=069, \log 7=084$, $\log 11=104$ )

The depression in freezing point observed for a formic acid solution of concentration $05\, mL\, L ^{-1}$ is $00405^{\circ} C$ Density of formic acid is $105 \, g \, mL ^{-1}$ The Van't Hoff factor of the formic acid solution is nearly : (Given for water $k _{ f }=186 \, K \, kg \, mol ^{-1}$ )

Which of the following sets of quantum numbers is not allowed?

The reaction of $H _2 O _2$ with potassium permanganate in acidic medium leads to the formation of mainly:

1g of a carbonate (M₂CO₃) on treatment with excess HCl produces 0.01 mol of CO₂ .The molar mass of M₂CO₃ is g mol^-1. (Nearest integer)

The orbital angular momentum of an electron in 3s orbital is  \(\frac{xh}{2π}\) The value of x is___.

20 mL of 0.1 M NaOH is added to 50 mL of 0.1 M acetic acid solution. The pH of the resulting solution is____ x 10^-2 (Nearest integer) 
Given: pKa (CH₃COOH) = 4.76 
log 2 = 0.30 
log 3 = 0.48

At 298 K, the standard reduction potential for Cu²⁺/Cu electrode is 0.34 V. 
Given: Ksp Cu(OH)2 = 1 × 10^-20 
Take \(\frac{2.303RT}{F}\)= 0.059V 
The reduction potential at pH = 14 for the above couple is (-)x x 10^-2 V. 
The value of x is_____.

A(g) → 2B(g) + C(g) is a first order reaction. The initial pressure of the system was found to be 800 mm Hg which increased to 1600 mm Hg after 10 min. The total pressure of the system after 30 min will be ___mm Hg. (Nearest integer)

0.400 g of an organic compound (X) gave 0.376 g of AgBr in Carius method for estimation of bromine. % of bromine in the compound (X) is____
(Given: Molar mass AgBr=188g mol^-1)

Let the sets A and B denote the domain and range respectively of the function \(f(x)=\frac{1}{\sqrt[x]-x}\) where [x] denotes the smallest integer greater than or equal to x . Then among the statements 
(S1) : A ∩ B = (1, ∞) – N and  
(S2) : A ∪ B = (1, ∞)