List of top Questions asked in JEE Main

It is observed that characteristic $X$-ray spectra of elements show regularity When frequency to the power " $n$ " ie $v^n$ of $X$-rays emitted is plotted against atomic number " $Z$ ", following graph is obtained

Choose the correct representation of conductometric titration of benzoic acid vs sodium hydroxide

Identify the correct statements about alkali metals
A. The order of standard reduction potential $\left( M ^{+} \mid M \right)$for alkali metal ions is $Na > Rb > Li$
B. $CsI$is highly soluble in water.
C. Lithium carbonate is highly stable to heat.
D. Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
E. All the alkali metal hydrides are ionic solids.
Choose the correct answer from the options given below:

Figures (a), (b), (c) and (d) show variation of force with time The impulse is highest in figure

A student has studied the decomposition of a gas AB₃ at 25^∘C. He obtained the following data.

p(mmHg)	50	100	200	400
$relative\space t_{1/2}(s)$	4	2	1	0.5

The order of the reaction is……….

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): Gypsum is used for making fireproof wall boards
Reason (R): Gypsum is unstable at high temperatures
In the light of the above statements, choose the correct answer from the options given below :

Choose the correct colour of the product for the following reaction

The hybridization and magnetic behaviour of cobalt ion in $\left[ Co \left( NH _3\right)_6\right]^{3+}$ complex, respectively is

Given below are two statements:
Statement I : Pure Aniline and other arylamines are usually colourless.
Statement II : Arylamines get coloured on storage due to atmospheric reduction.
Choose the correct answer

If the foot of the perpendicular drawn from $(1,9,7)$ to the line passing through the point $(3,2,1)$ and parallel to the planes $x+2 y+z=0$ and $3 y-z=3$ is $(\alpha, \beta, \gamma)$, then $\alpha+\beta+\gamma$ is equal to

The number of real solutions of the equation $3\left(x^2+\frac{1}{x^2}\right)-2\left(x+\frac{1}{x}\right)+5=0$, is

If $f(x)=\frac{2^{2 x}}{2^{2 x}+2}, x \in R$, then $f\left(\frac{1}{2023}\right)+f\left(\frac{2}{2023}\right)+\ldots+f\left(\frac{2022}{2023}\right)$ is equal to

The value of $\left(\frac{1+\sin \frac{2 \pi}{9}+i \cos \frac{2 \pi}{9}}{1+\sin \frac{2 \pi}{9}-i \cos \frac{2 \pi}{9}}\right)^3$ is

Let $f(x)$ be a function such that $f(x+y)=f(x) \cdot f(y)$ for all $x, y \in$ N If $f(1)=3$ and $\displaystyle\sum_{k=1}^n f(k)=3279$, then the value of $n$ is

The set of all values of $a$ for which $\displaystyle\lim _{x \rightarrow a}([x-5]-[2 x+2])=0$,where $[\propto]$ denotes the greatest integer less than or equal to $\propto$ is equal to

The equations of the sides $AB$ and $AC$ of a triangle $ABC$ are $(\lambda+1) x+\lambda y=4$ and $\lambda x+(1-\lambda) y+\lambda=0$ respectively Its vertex $A$ is on the $y$ - axis and its orthocentre is $(1,2)$ The length of the tangent from the point $C$ to the part of the parabola $y^2=6 x$ in the first quadrant is :

The locus of the mid points of the chords of the circle $C_1:(x-4)^2+(y-5)^2=4$ which subtend an angle $\theta_i$ at the centre of the circle $C_1$, is a circle of radius $r_i$ If $\theta_1=\frac{\pi}{3}, \theta_3=\frac{2 \pi}{3}$ and $r_1^2=r_2^2+r_3^2$, then $\theta_2$ is equal to

Let the plane containing the line of intersection of the planes $P 1: x+(\lambda+4) y+z=1$ and $P 2: 2 x+$ $y+z=2$ pass through the points $(0,1,0)$ and $(1,0,1)$ Then the distance of the point $(2 \lambda, \lambda,-\lambda)$ from the plane $P 2$ is

Let the six numbers $a_1, a_2, a_3, a_4, a_5, a_6$, be in AP and $a_1+a_3=10$ If the mean of these six numbers is $\frac{19}{2}$ and their variance is $\sigma^2$, then $8 \sigma^2$ is equal to :

The number of square matrices of order 5 with entries from the set $\{0,1\}$, such that the sum of all the elements in each row is 1 and the sum of all the elements in each column is also 1 , is

The number of integers, greater than $7000$ that can be formed, using the digits $3,5,6,7,8$ without repetition, is

If the system of equations $ x+2 y+3 z=3$ $ 4 x+3 y-4 z=4 $ $ 8 x+4 y-\lambda z=9+\mu$ has infinitely many solutions, then the ordered pair $(\lambda, \mu)$ is equal to :

In AM modulation, a signal is modulated on a carrier wave such that maximum and minimum amplitude are found to be $6 V$ and $2 V$ respectively The modulation index is

The electric current in a circular coil of 2 turns produces a magnetic induction $B _1$ at its centre The coil is unwound and is rewound into a circular coil of 5 turns and the same current produces a magnetic induction $B _2$ at its centre The ratio of $\frac{ B _2}{ B _1}$ is :

A drop of liquid of density ρ is floating half immersed in a liquid of density σ and surface tension 7.5×10⁻⁴Ncm⁻¹. The radius of drop in cm will be : ( Take : g=10 m/s²)