List of top Physics Questions on Physics asked in IIT JAM PH

A parallel plate capacitor having plate area of 50 cm$^2$ and separation of 0.1 mm is completely filled with a dielectric (dielectric constant $ K = 10 $). The capacitor is connected to a 10 kΩ resistance and an alternating voltage $ v = 10 \sin(100\pi t) $, as shown in the figure. The switch $ S $ is initially open and then closed at $ t = 0 $. The ratio of the displacement current in the capacitor, to the current in the resistance, at time $ t = \frac{2}{\pi} $ seconds is .......... (Round off to three decimal places).

An RC circuit is connected to two dc power supplies, as shown in the figure. With switch $ S $ open, the capacitor is fully charged. $ S $ is then closed at time $ t = 0 $. The voltage across the capacitor at $ t = 2.4 \, \text{ms} $ is ................ V (Round off to one decimal place).

A time independent conservative force $ \vec{F} $ has the form, $ \vec{F} = 3y\hat{i} + f(x, y)\hat{j} $. Its magnitude at $ x = y = 0 $ is 8. The allowed form(s) of $ f(x, y) $ is (are):

Four charges are placed very close to each other, as shown. The separation between the two charges on the y-axis is $ a $. The separation between the two charges on the x-axis is also $ a $. The leading order (non-vanishing) form of the electrostatic potential, at point $ P $, at a distance $ r $ from the origin ($ r \gg a $), is:

For the given circuit, the output $ Y $ is:

Let $(x, y)$ denote the coordinates in a rectangular Cartesian coordinate system $ C $. Let $(x', y')$ denote the coordinates in another coordinate system $ C' $ defined by
\[ x' = 2x + 3y, \quad y' = -3x + 4y \] The area element in $ C' $ is:

Twenty non-interacting spin $ \frac{1}{2} $ particles are trapped in a three-dimensional simple harmonic oscillator potential of frequency $ \omega $. The ground state energy of the system, in units of $ \hbar \omega $, is ......... .

For the Boolean expression $ Y = A B C + A' B C + A B' C + A' B' C $, the number of combinations for which the output $ Y = 1 $ is .............. .

Consider the following differential equation that describes the oscillations of a physical system:
\[ \alpha \frac{d^2y}{dt^2} + \beta \frac{dy}{dt} + \gamma y = 0 \] If $ \alpha $ and $ \beta $ are held fixed, and $ \gamma $ is increased, then:

The rms velocity of molecules of oxygen gas is given by $ v = \sqrt{\frac{3kT}{m}} $ at some temperature $ T $. The molecules of another gas have the same rms velocity at temperature $ T' = \frac{T}{16} $. The second gas is:

At $ t = 0 $, $ N_0 $ number of radioactive nuclei $ A $ start decaying into $ B $ with a decay constant $ \lambda_a $. The daughter nuclei $ B $ decay into nuclei $ C $ with a decay constant $ \lambda_b $. Then, the number of nuclei $ B $ at small time $ t $ (to the leading order) is:

Arrange the following telescopes, where $ D $ is the telescope diameter and $ \lambda $ is the wavelength, in order of decreasing resolving power:
I. $ D = 100\,\text{m}, \lambda = 21\,\text{cm} $
II. $ D = 2\,\text{m}, \lambda = 500\,\text{nm} $
III. $ D = 1\,\text{m}, \lambda = 100\,\text{nm} $
IV. $ D = 2\,\text{m}, \lambda = 10\,\text{mm} $

An object of density $ \rho $ is floating in a liquid with 75% of its volume submerged. The density of the liquid is:

The Zener current $ I_Z $ for the given circuit is .............. mA.

The flux of the function $ \mathbf{F} = (y^2) \hat{x} + (3xy - z^2) \hat{y} + (4yz) \hat{z} $ passing through the surface ABCD along $ \hat{n} $ is ............

During the charging of a capacitor C in a series RC circuit, the typical variations in the magnitude of the charge $q(t)$ deposited on one of the capacitor plates, and the current $i(t)$ in the circuit, respectively are best represented by

In the given phase diagram for a pure substance, regions I, II, III, IV, respectively represent

The output of the following logic circuit can be simplified to \[ \text{(Logic circuit diagram provided)} \]

A classical particle has total energy $ E $. The plot of potential energy $ U(r) $ as a function of distance $ r $ from the centre of force located at $ r = 0 $ is shown in the figure. Which of the regions are forbidden for the particle?

The decimal equivalent of the binary number 110.101 is ................

The 7th bright fringe in the Young’s double slit experiment using a light of wavelength 550 nm shifts to the central maxima after covering the two slits with two sheets of different refractive indices $n_1$ and $n_2$ but having the same thickness 6 µm. The value of $ |n_1 - n_2| $ is .............

An object of 2 cm height is placed at a distance of 30 cm in front of a concave mirror with radius of curvature 40 cm. The height of the image is ............. cm.

For an underdamped harmonic oscillator with velocity $ v(t) $,

Consider a classical particle subjected to an attractive inverse-square force field. The total energy of the particle is $ E $ and the eccentricity is $ \epsilon $. The particle will follow a parabolic orbit if

A $\gamma$-ray photon emitted from a $^{137}$Cs source collides with an electron at rest. If the Compton shift of the photon is $3.25 \times 10^{-13}$ m, then the scattering angle is closest to (Planck’s constant $h = 6.626 \times 10^{-34}$ J s, electron mass $m_e = 9.109 \times 10^{-31}$ kg and velocity of light in free space $c = 3 \times 10^8$ m/s)