List of top Physics Questions asked in JEE Main

A radioactive nucleus decays by two different process The half life of the first process is 5 minutes and that of the second process is $30 s$. The effective half-life of the nucleus is calculated to be $\frac{\alpha}{11}$ s The value of $\alpha$ is _______
A nucleus disintegrates into two smaller parts, which have their velocities in the ratio $3: 2$ The ratio of their nuclear sizes will be $\left(\frac{x}{3}\right)^{\frac{1}{3}}$ The value of ' $x$ ' is:-
Assume that protons and neutrons have equal masses Mass of a mucleon is $16 \times 10^{-27} kg$ and radius of nucleus is $15 \times 10^{-15} A ^{1 / 3} m$ The approximate ratio of the nuclear density and water density is $n \times 10^{13}$ The value of $n$ is ___
The mass of proton, neutron and helium nucleus are respectively $10073\, u$, $10087\, u$ and $40015\, u$ The binding energy of helium nucleus is:
A capacitor has capacitance $5 \mu F$ when it's parallel plates are separated by air medium of thickness d A slab of material of dielectric constant $15$ having area equal to that of plates but thickness $\frac{d}{2}$ is inserted between the plates Capacitance of the capacitor in the presence of slab will be ___$\mu F$
Potential at the surface of a uniformly charged non-conducting sphere is V. Then the potential at its centre is

Which of the following correctly represents the variation of electric potential (V) of a charged spherical conductor of radius (R) with radial distance (r) from the center?

A point charge of $10\, \mu C$ is placed at the origin At what location on the $X$-axis should a point charge of $40 \, \mu C$ be placed so that the net electric field is zero at $x=2 \, cm$ on the $X$-axis?

A parallel plate capacitor with plate area A and plate separation d is filled with a dielectric material of dielectric constant K = 4. The thickness of the dielectric material is x, where x < d. Let C1 and C2 be the capacitance of the system for \(x =\) \(\frac{1}{3}d\) and \(x=\frac{2}{3}d\), respectively. If C1 = 2μF, the value of C2 is _______ μF.

Find the energy stored in the capacitor in a given circuit. 
A capacitor of capacitance $900\, \mu F$ is charged by a $100\, V$ battery The capacitor is disconnected from the battery and connected to another uncharged identical capacitor such that one plate of uncharged capacitor connected to positive plate and another plate of uncharged capacitor connected to negative plate of the charged capacitor The loss of energy in this process is measured as $x \times 10^{-2} J$ The value of $x$ is ______

A parallel plate capacitor with air between the plate has a capacitance of \(15\, pF\) The separation between the plate becomes twice and the space between them is filled with a medium of dielectric constant \(3.5\). Then the capacitance becomes \(\frac{x}{4} pF\) The value of \(x\) is _______

As shown in the figure, a point charge $Q$ is placed at the centre of conducting spherical shell of inner radius $a$ and outer radius $b$. The electric field due to charge $Q$ in three different regions I, II and III is given by: (I: r $<$ a, II: $a $<$ r $<$ b$, III: $r$>$b)$
Electric Field
A parallel plate capacitor with plate area A and plate separation d is filed with a dielectric material of dielectric constant K = 4. The thickness of the dielectric material is x, where \(x < d\).
A parallel plate capacitor with plate area A
Let C1 and C2 be the capacitance of the system for \(x=\frac{1}{3d}\) and \(x=\frac{2d}{3}\), respectively. If \(C_1 = 2μF\), the value of C2 is __________μF.

The equivalent resistance between \( A \) and \( B \) as shown in the figure is:
The equivalent resistance between

Find the equivalent resistance across A and B for given circuit.
equivalent resistance across A and B
A null point is found at 200 cm in potentiometer when cell in secondary circuit is shunted by 5Ω. When a resistance of 15Ω is used for shunting, null point moves to 300 cm. The internal resistance of the cell is _______ Ω.
When two resistances 𝑅1 and 𝑅2 connected in series and introduced into the left gap of a meter bridge and a resistance of 10Ω is introduced into the right gap, a null point is found at 60 cm from left side. When 𝑅1 and 𝑅2 are connected in parallel and introduced into the left gap, a resistance of 3Ω is introduced into the right-gap to get null point at 40 cm from left end. The product of 𝑅1𝑅2 is _______ Ω2.
In a metre bridge experiment, the balance point is obtained if the gaps are closed by \(2 \Omega\) and \(3 \Omega\). A shunt of \(X \Omega\) is added to \(3 \Omega\) resistor to shift the balancing point by 22.5 cm. The value of X is _______ .
A series combination of resistor of resistance 100 Ω, inductor of inductance 1 H and capacitor of capacitance 6.25 µF is connected to an ac source. The quality factor of the circuit will be ______
10 resistors each of resistance 10Ω can be connected in such as to get maximum and minimum equivalent resistance. The ratio of maximum and minimum equivalent resistance will be_______ .
The distance between two plates of a capacitor is \(d\) and its capacitance is \(C_1\), when air is the medium between the plates. If a metal sheet of thickness \(\frac {2d}{3}\) and of the same area as plate is introduced between the plates, the capacitance of the capacitor becomes \(C_2\). The ratio \(\frac {C_2}{C_1}\) is
A rectangular parallelopiped is measured as 1 cm × 1 cm × 100 cm. If its specific resistance is 3 × 10-7 Ωm, then the resistance between its two opposite rectangular faces will be _____ ×10-7 Ω.
resistors
The current flowing through \(R_2\) is
Two identical cells each of emf 1.5 V are connected in series across a 10Ω resistance. An ideal voltmeter connected across 10 resistance reads 1.5 V. The internal resistance of each cell is ______Ω.