List of top Questions asked in JEE Main

Five identical convex lenses are placed one after the other in close contact. The power of this arrangement is 25 D. Then, the power of one such lens is

A gas is kept in a vessel of volume 0.2 m³ at temperature 300 K and pressure 1 bar. The molar heat capacity of gas at constant volume is 5 cal/mol K. The heat (kcal) required to raise the temperature to 400 K is ______.

Which of the following graph correctly represent the variation

δ = \frac{d V}{V d T}

for an ideal gas at constant pressure?

The de Broglie wavelength of an electron moving with a velocity 1.5 × 10⁸ m/s is equal to that of a photon. The ratio of the energy of the photon to the kinetic energy of the electron is ______.

As per the Bohr model, the minimum energy (in eV) required to remove an electron from the ground state of a double ionized Li atom (Z = 3) is

A uniform solid sphere of radius

R

has a spherical hole or radius

a

in it. Find the position of its center of mass.

In a discharging RC circuit, at what time the electrical potential energy will become the half of its initial value? [in terms of time constant of RC circuit,]

In the pure inductive circuit, the curves between frequency

f

and reciprocal of inductive reactance

\frac{1}{X_{L}}

is:

As given in the figure, a series circuit connected across a

200 V, 60 H z

line consists of a capacitor of capacitive reactance

30 Ω

, a non-inductive resistor of

44 Ω

, and a coil of inductive resistance

90 Ω

and resistance

36 Ω

. The power dissipated in the coil is?

A current i is flowing through the loop. The direction of the current and the shape of the loop are as shown in the figure.The magnetic field at the centre of the loop is,

\frac{μ_{0} i}{R}

times

[ MA = R , MB = 2R,

∠

DMA = 90°]

Consider following statements.
S1:

IUPAC name is 4-chloro-1,3-dinitrobenzene
S2:

IUPAC name is 2-methylaniline

We have two complexes, [Fe(H₂O)₆]²⁺ and [Cu(H₂O)₆]²⁺ , the magnetic properties respectively are

Which of the following statement is incorrect-

IUPAC name of complex compound [Pt(Br)₂(PPh₃)₂].

For a certain reaction, ΔH_r is 400 kJ/mol and ΔS=0.2 kJ/mol K. Above what minimum temperature in Kelvin, the reaction becomes spontaneous.

Among the following anions, identify the anion which gives pale yellow precipitate with aq. AgNO₃. The precipitate is partially soluble in aq. NH₄OH solution.

Identify the product formed in the following reaction:

If the complex number (1 + 2i cosθ) / (1 - 3i cosθ) is purely imaginary, then find the number of values of θ in the interval [-2π, 2π].

A ray of light coming from (3, 1) incident on 2x + y = 6 and deflected ray passing through (7, 2). If equation of incident ray is ax + by + 1 = 0, then a² + b² + 3ab =

A ray of light passing through (1, 2) after reflecting on x-axis at point Q passes through R(3, 4). If S(h, k) is such that PQRS is a parallelogram, then find the value of hk².

If $\frac{1}{(1+d)(1+2d)}+\frac{1}{(1+2d)(1+3d)}+...+\frac{1}{(1+9d)(1+10d)}=1,$ then the value of 50d is____. (d > 0)

If the initial pressure of a gas is 0.03 atm, the mass of the gas adsorbed per gram of the adsorbent is ______ × 10^–2 g.

Let 'd' be the perpendicular distance from the centre of the ellipse

\frac{x^{2}}{a^{2}} + \frac{y^{2}}{b^{2}}

= 1 to the tangent drawn at a point P on the ellipse. If F1 and F are two foci of the ellipse, then (PF1 - PF)²is equal to;

2

g of a base whose equivalent weight is

40

reacts with

3 g

of an acid. The equivalent weight of the acid is:

The value of $\frac{1\times 2^2+2\times3^2+...+100\times (101)^2}{1^2 \times 2\times2^2 \times3+...+100^2 \times 101}$