List of top Questions asked in JEE Main

The actual value of resistance $R$, shown in the figure is $30 \Omega $. This is measured in an experiment as shown using the standard formula $R = \frac{V}{I}$ , where $V$ and $I$ are the readings of the voltmeter and ammeter, respectively. If the measured value of $R$ is $5\%$ less, then the internal resistance of the voltmeter is :

A rigid square loop of side 'a' and carrying current I$_2$ is lying on a horizontal surface near a long current I$_1$ carrying wire in the same plane as shown in figure. The net force on the loop due to wire will be :

Homoleptic octahedral complexes of a metal ion '${M^{3+} }$' with three monodentate ligands and $L_1, L_2, L_3$ absorb wavelengths in the region of green, blue and red respectively. The increasing order of the ligand strength is :

The peptide that gives positive ceric ammonium nitrate and carbylamine tests is :

The Mond process is used for the

One of the two identical conducting wires of length $L$ is bent in the form of a circular loop and the other one into a circular coil of $N$ identical turns. If the same current is passed in both, the ratio of the magnetic field at the central of the loop $(B_L)$ to that at the centre of the coil $(B_C)$ , i.e., $R \frac{B_L}{B_C}$ will be

A $20$ Henry inductor coil is connected to a $10$ ohm resistance in series as shown in figure. The time at which rate of dissipation of energy (joule's heat) across resistance is equal to the rate at which magnetic energy is stored in the inductor is :

Determine the charge on the capacitor in the following circuit :

In the circuit shown, the switch $S_1$ is closed at time $t = 0$ and the switch $S_2$ is kept open. At some later time $(t_0)$, the switch $S_1$ is opened and $S_2$ is closed. The behavious of the current $I$ as a function of time $'t'$ is given by :

The aerosol is a kind of colloid in which :

The compound used in the treatment of lead poisoning is :

The concentration of dissolved oxygen $(DO)$ in cold water can go upto :

The correct statements among (a) to (b) are: (a) saline hydrides produce $H_2$ gas when reacted with ${H2O}$. (b) reaction of $LiAH_4$ with $BF_3$ leads to $B_2H_6$. (c) $PH_3$ and $CH_4$ are electron - rich and electronprecise hydrides, respectively. (d) HF and $CH_4$ are called as molecular hydrides.

The decreasing order of electrical conductivity of the following aqueous solutions is : 0.1 M Formic acid (A), 0.1 M Acetic acid (B) 0.1 M Benzoic acid (C)

Two identical breakers A and B contain equal volumes of two different liquids at $60^{\circ}C$ each and left to cool down. Liquid in A has density of $8 \times 10^2 \; kg/m^3$ and sp ecific heat o f 2000 J $kg^{-1} \; K^{-1}$ while liquid in B has density o f 103 kg m-3 and sp ecific heat o f 4000 J $kg^{-1} K^{-1}$. Which of the following best describes their temperature versus time graph schematically? (assume the emissivity of both the beakers to be the same)

Molal depression constant for a solvent is $4.0\, kg\, mol^{-1}$. The depression in the freezing point of the solvent for $0.03\, mol\, kg^{-1}$ solution of $ {K2SO4}$ is : (Assume complete dissociation of the electrolyte)

Peptization is a :

The mean and the median of the following ten numbers in increasing order $10, 22, 26, 29, 34, x 42, 67, 70,\, y$ are $42$ and $35$ respectively, then $\frac{y}{x}$ is equal to :

The plane which bisects the line segment joining the points (-3,-3,4) and (3,7,6) at right angles, passes through which one of the following points ?

The primary pollutant that leads to photochemical smog is :

Two plane mirrors arc inclined to each other such that a ray of light incident on the first mirror $(M_1)$ and parallel to the second mirror $(M_2)$ is finally reflected from the second mirror $(M_2)$ parallel to the first mirror $(M_1)$. The angle between the two mirrors will be :

The correct statements among I to III are : (I) Valence bond theory cannot explain the color exhibited by transition metal complexes. (II) Valence bond theory can predict quantitatively the magnetic properties of transtition metal complexes. (III) Valence bond theory cannot distinguish ligands as weak and strong field ones.

The amount of sugar $ {(C_{12}H_{22}O_{11})}$ required to prepare $2\, L$ of its $0.1\, M$ aqueous solution is :

If the standard electrode potential for a cell is 2 V at 300 K, the equilibrium constant (K) for the reaction ${Zn(s) + cu^{2+} (aq) <=> Zn^{2+} (aq) + Cu(s)}$ at 300 K is approximately. ${(R = 8 \; JK^{-1} \; mol^{-1} , F = 96000 \; C \; mol^{-1})}$

The plane through the intersection of the planes $x + y + z = 1$ and $2x + 3y - z + 4 = 0$ and parallel to y-axis also passes through the point :