List of top Questions asked in JEE Main

Which of the following metals can be extracted through alkali leaching technique?

An indicator ' X ' is used for studying the effect of variation in concentration of iodide : on the rate of reaction of iodide ion with $H_2O_2 $ at room temp. The indicator ' X ' forms blue colored complex with compound ' A ' present in the solution. The indicator ' X ' and compound 'A' respectively are

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Beryllium has less negative value of reduction potential compared to the other alkaline earth metals
Reason R: Beryllium has large hydration energy due to small size of $Be ^{2+}$ but relatively large value of atomization enthalpy
In the light of the above statements, choose the most appropriate answer from the options given below

A car travels a distance of ' $x$ ' with speed $v_1$ and then same distance ' $x$ ' with speed $v_2$ in the same direction The average speed of the car is:

For designing a voltmeter of range 50 V and an ammeter of range 10 mA using a galvanometer which has a coil of resistance 54Ω showing a full scale deflection for 1 mA as in figure.

(A) for voltmeter R ≈ 50 kΩ
(B) for ammeter r ≈ 0.2Ω
(C) for ammeter r ≈ 6Ω
(D) for voltmeter R ≈ 5 kΩ (E) for voltmeter R ≈ 500Ω
Choose the correct answer from the options given below :

A particle is executing Simple Harmonic Motion (SHM). The ratio of potential energy and kinetic energy of the particle when its displacement is half of its amplitude will be

The source of time varying magnetic field may be
(A) a permanent magnet
(B) an electric field changing linearly with time
(C) direct current
(D) a decelerating charge particle
(E) an antenna fed with a digital signal
Choose the correct answer from the options given below:

If de-Broglie wavelength is $\lambda$ when energy is E. Find the wavelength at $\frac{E}{4}$ (Kinetic Energy).

The free space inside a current carrying toroid is filled with a material of susceptibility $ 2 \times 10^3 $. The percentage increase in the value of magnetic field inside the toroid will be:

Given below are two statements:
Statement I : The diamagnetic property depends on temperature.
Statement II : The included magnetic dipole moment in a diamagnetic sample is always opposite to the magnetizing field.
In the light of given statement, choose the correct answer from the options given below:

A plane electromagnetic wave of frequency 20 MHz propagates in free space along x-direction. At a particular space and time, $\overrightarrow E =6.6 \;\hat jV/m .$What is $\overrightarrow B$ at this point ?

Young's moduli of the material of wires A and B are in the ratio of 1:4, while its area of cross section are in the ratio of 1:3. If the same amount of load is applied to both the wires, the amount of elongation produced in the wires A and B will in the ratio of
[Assume length of wires A and B are same]

For the logic circuit shown, the output waveform at Y is:

An ice cube has a bubble inside. When viewed from one side the apparent distance of the bubble is 12 cm. When viewed from the opposite side, the apparent distance of the bubble is observed as 4 cm. If the side of the ice cube is 24 cm, the refractive index of the ice cube is:

The ratio of average electric energy density and total average energy density of electromagnetic wave is:

In an electromagnetic wave, at an instant and at a particular position, the electric field is along the negative z-axis and magnetic field is along the positive x-axis. Then the direction of propagation of electromagnetic wave is

For the given radioactive decay $^{298}_{94}X → ^{294}_{92}X + ^{4}_{2}ɑ + Q$ - value, binding energy per nucleon of X, Y and ɑ are a, b and c. The Q - value is equal to

A flask contains Hydrogen and Argon in the ratio 2:1 by mass. The temperature of the mixture is 30°C. The ratio of average kinetic energy per molecule of the two gases (K argon/K hydrogen) is:
(Given: Atomic Weight of Ar = 39.9)

An alternating voltage source $V =260 \sin (628 t )$ is connected across a pure inductor of $5 mH$ Inductive reactance in the circuit is :

Variation of magnetic field through a coil of area 4 m² is shown in figure. What is the EMF induced in the coil (in mV)?

A body weight W, is projected vertically upwards from earth's surface to reach a height above the earth which is equal to nine times the radius of earth The weight of the body at that height will be :

An electron of a hydrogen like atom, having $Z=4$, jumps from $4^{\text {th }}$ energy state to $2^{\text {nd }}$ energy state. The energy released in this process, will be :
$($ Given Rch $=136 eV )$
Where $R =$ Rydberg constant
$c =$ Speed of light in vacuum
$h =$ Planck's constant

A body is doing SHM with amplitude A. When it is at $ x =+ \frac{A}{2}$ , find ratio of kinetic energy to potential energy.

The ratio of speed of sound in hydrogen gas to the speed of sound in oxygen gas at the same temperature is:

Which of the following Maxwell's equation is valid for time varying conditions but not valid for static conditions: