List of top Physics Questions asked in JEE Main

Three bodies A, B and C have equal kinetic energies and their masses are 400 g, 1.2 kg and 1.6 kg respectively. The ratio of their linear momenta is :

There are 100 divisions on the circular scale of a screw gauge of pitch 1 mm. With no measuring quantity in between the jaws, the zero of the circular scale lies 5 divisions below the reference line. The diameter of a wire is then measured using this screw gauge. It is found the 4 linear scale divisions are clearly visible while 60 divisions on circular scale coincide with the reference line. The diameter of the wire is :

Water boils in an electric kettle in 20 minutes after being switched on. Using the same main supply, the length of the heating element should be ………….. to …………. times of its initial length if the water is to be boiled in 15 minutes.

A diatomic gas (\( \gamma = 1.4 \)) does 100 J of work in an isobaric expansion. The heat given to the gas is:

Small water droplets of radius 0.01 mm are formed in the upper atmosphere and falling with a terminal velocity of 10 cm/s. Due to condensation, if 8 such droplets are coalesced and formed a larger drop, the new terminal velocity will be ………..cm/s.

Two slits are 1 mm apart and the screen is located 1 m away from the slits. A light wavelength \( 500 \, \text{nm} \) is used. The width of each slit to obtain 10 maxima of the double slit pattern within the central maximum of the single slit pattern is \(\dots\) \(\times \, 10^{-4} \, \text{m}\).

In the given circuit, the terminal potential difference of the cell is :

A coil of negligible resistance is connected in series with \(90 \, \Omega\) resistor across \(120 \, \text{V}, \, 60 \, \text{Hz}\) supply. A voltmeter reads \(36 \, \text{V}\) across resistance. Inductance of the coil is:

An alternating emf \( E = 110\sqrt{2} \sin 100t \, \text{volt} \) is applied to a capacitor of \( 2\mu\text{F} \), the rms value of current in the circuit is \(\dots\) \(\text{mA}\).

A proton and an electron have the same de Broglie wavelength. If \(K_p\) and \(K_e\) be the kinetic energies of proton and electron respectively. Then choose the correct relation:

If \(M_0\) is the mass of isotope \(^{{12}}_{{5}}B\), \(M_p\) and \(M_n\) are the masses of proton and neutron, then nuclear binding energy of isotope is:

An object of mass \( 0.2 \, \text{kg} \) executes simple harmonic motion along the \( x \)-axis with a frequency of \( \left( \frac{25}{\pi} \right) \, \text{Hz} \). At the position \( x = 0.04 \, \text{m} \), the object has kinetic energy \( 0.5 \, \text{J} \) and potential energy \( 0.4 \, \text{J} \). The amplitude of oscillation is \(\dots\) \(\text{cm}\).

The binding energy of a certain nucleus is \(18 \times 10^8 \, \text{J}\). How much is the difference between the total mass of all the nucleons and the nuclear mass of the given nucleus?

A given object takes \(n\) times the time to slide down \(45^\circ\) rough inclined plane as it takes the time to slide down an identical perfectly smooth \(45^\circ\) inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is:

A mixture of one mole of a monoatomic gas and one mole of a diatomic gas (rigid) are kept at room temperature (\(27^\circ \text{C}\)). The ratio of specific heat of gases at constant volume respectively is:

A heater is designed to operate with a power of 1000 W in a 100 V line. It is connected in combination with a resistance of 10 \(\Omega\) and a resistance \(R\), to a 100 V mains as shown in the figure. For the heater to operate at 62.5 W, the value of \(R\) should be \(\dots\) \(\Omega\).

The coercivity of a magnet is 5 × 10³ A/m. The amount of current required to be passed in a solenoid of length 30 cm and the number of turns 150, so that the magnet gets demagnetised when inside the solenoid is ………A.

A potential divider circuit is connected with a dc source of 20 V, a light emitting diode of glow in voltage 1.8 V and a zener diode of breakdown voltage of 3.2 V. The length (PR) of the resistive wire is 20 cm. The minimum length of PQ to just glow the LED is …………. cm.

A string is wrapped around the rim of a wheel of moment of inertia $0.40 \, \text{kgm}^2$ and radius $10 \, \text{cm}$. The wheel is free to rotate about its axis. Initially, the wheel is at rest. The string is now pulled by a force of $40 \, \text{N}$. The angular velocity of the wheel after $10 \, \text{s}$ is $x \, \text{rad/s}$, where $x$ is ______.

At the centre of a half ring of radius $R = 10 \, \text{cm}$ and linear charge density $4n \, \text{C m}^{-1}$, the potential is $x \pi \, \text{V}$. The value of $x$ is ______.

A galvanometer has a coil of resistance \(200 \, \Omega\) with a full scale deflection at \(20 \, \mu A\). The value of resistance to be added to use it as an ammeter of range (0–20) mA is:

A thin circular disc of mass \(M\) and radius \(R\) is rotating in a horizontal plane about an axis passing through its centre and perpendicular to its plane with angular velocity \(\omega\). If another disc of same dimensions but of mass \(\frac{M}{2}\) is placed gently on the first disc co-axially, then the new angular velocity of the system is:

The equivalent resistance between A and B is:

Two persons pull a wire towards themselves. Each person exerts a force of $200 \, \text{N}$ on the wire. Young’s modulus of the material of the wire is $1 \times 10^{11} \, \text{N m}^{-2}$. Original length of the wire is $2 \, \text{m}$ and the area of cross-section is $2 \, \text{cm}^2$. The wire will extend in length by ______ $\mu \text{m}$.

If \( \epsilon_0 \) is the permittivity of free space and \( E \) is the electric field, then \( \epsilon_0 E^2 \) has the dimensions: