JEE Main 2023 Physics Paper: 30 Jan, Shift 1

In a series LR circuit with $X_L = R$, power factor P1. If a capacitor of capacitance C with $X_C = X_L$ is added to the circuit the power factor becomes P2. The ratio of P1 to P2 will be:

Speed of an electron in Bohr's $7$th orbit for Hydrogen atom is $3.6 \times 10^{6}\text{ m/s}$. The corresponding speed of the electron in $3$rd orbit, in $\text{m/s}$ is:

A capacitor of capacitance $900\ \mu\text{F}$ is charged by a $100\text{ V}$ 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 $x\times 10^{-2}\text{ J}$. The value of $x$ is _____________.

The charge flowing in a conductor changes with time as $Q(t) = \alpha t - \beta t^{2} + \gamma t^{3}$. Where $\alpha, \beta$ and $\gamma$ are constants. Minimum value of current is:

In the following circuit, the magnitude of current I1, is ___________ A.

A small object at rest, absorbs a light pulse of power $20\text{ mW}$ and duration $300\text{ ns}$. Assuming speed of light as $3 \times 10^{8}\text{ m/s}$, the momentum of the object becomes equal to:

As per the given figure, if $\frac{dI}{dt} = -1\text{ A/s}$ then the value of $V_{AB}$ at this instant will be ____________ $\text{V}$.

A point source of light is placed at the centre of curvature of a hemispherical surface. The source emits a power of $24\text{ W}$. The radius of curvature of hemisphere is $10\text{ cm}$ and the inner surface is completely reflecting. The force on the hemisphere due to the light falling on it is ____________ $\times 10^{-8}\text{ N}$.

Electric field in a certain region is given by $\vec{E} = \left(\frac{A}{x^2}\hat{i} + \frac{B}{y^3}\hat{j}\right)$. The $\text{SI}$ unit of $A$ and $B$ are:

Two isolated metallic solid spheres of radii $R$ and $2R$ are charged such that both have same charge density $\sigma$. The spheres are then connected by a thin conducting wire. If the new charge density of the bigger sphere is $\sigma'$. The ratio $\frac{\sigma'}{\sigma}$ is:

If the gravitational field in the space is given as $\left(-\frac{K}{r^2}\right)$. Taking the reference point to be at $r = 2\text{ cm}$ with gravitational potential $V = 10\text{ J/kg}$. Find the gravitational potential at $r = 3\text{ cm}$ in SI unit (Given, that $K = 6\text{ J cm/kg}$)

Choose the correct relationship between Poisson ratio $(\sigma)$, bulk modulus (K) and modulus of rigidity $(\eta)$ of a given solid object:

A horse rider covers half the distance with $5\text{ m/s}$ speed. The remaining part of the distance was travelled with speed $10\text{ m/s}$ for half the time and with speed $15\text{ m/s}$ for other half of the time. The mean speed of the rider averaged over the whole time of motion is $\frac{x}{7}\text{ m/s}$. The value of $x$ is ___________.

Match Column-I with Column-II:

Choose the correct answer from the options given below:

The magnetic moments associated with two closely wound circular coils $A$ and $B$ of radius $r_A = 10\text{ cm}$ and $r_B = 20\text{ cm}$ respectively are equal if: (Where $N_A, I_A$ and $N_B, I_B$ are number of turns and current of $A$ and $B$ respectively)

A massless square loop, of wire of resistance $10\ \Omega$, supporting a mass of $1\text{ g}$, hangs vertically with one of its sides in a uniform magnetic field of $10^{3}\text{ G}$, directed outwards in the shaded region. A dc voltage $\text{V}$ is applied to the loop. For what value of $\text{V}$, the magnetic force will exactly balance the weight of the supporting mass of $1\text{ g}$?

(If sides of the loop $= 10\text{ cm},\ g = 10\text{ m s}^{-2}$)

The general displacement of a simple harmonic oscillator is $x = A\sin\omega t$. Let T be its time period. The slope of its potential energy (U) - time (t) curve will be maximum when $t = \frac{T}{\beta}$. The value of $\beta$ is ______________.

A person has been using spectacles of power $-1.0$ dioptre for distant vision and a separate reading glass of power $2.0$ dioptres. What is the least distance of distinct vision for this person:

In an experiment for estimating the value of focal length of converging mirror, image of an object placed at $40\text{ cm}$ from the pole of the mirror is formed at distance $120\text{ cm}$ from the pole of the mirror. These distances are measured with a modified scale in which there are 20 small divisions in $1\text{ cm}$. The value of error in measurement of focal length of the mirror is $\frac{1}{\text{K}}\text{ cm}$. The value of $\text{K}$ is __________.

A thin uniform rod of length $2\text{ m}$, cross sectional area '$A$' and density '$d$' is rotated about an axis passing through the centre and perpendicular to its length with angular velocity $\omega$. If value of $\omega$ in terms of its rotational kinetic energy $E$ is $\sqrt{\frac{\alpha E}{Ad}}$ then value of $\alpha$ is ______________.

The output waveform of the given logical circuit for the following inputs A and B as shown below, is:

The height of liquid column raised in a capillary tube of certain radius when dipped in liquid A vertically is, $5\text{ cm}$. If the tube is dipped in a similar manner in another liquid $B$ of surface tension and density double the values of liquid $A$, the height of liquid column raised in liquid $B$ would be __________ m.

The pressure $(P)$ and temperature ($T)$ relationship of an ideal gas obeys the equation $PT^{2} =$ constant. The volume expansion coefficient of the gas will be:

Heat is given to an ideal gas in an isothermal process.

A. Internal energy of the gas will decrease.

B. Internal energy of the gas will increase.

C. Internal energy of the gas will not change.

D. The gas will do positive work.

E. The gas will do negative work.

Choose the correct answer from the options given below:

In a screw gauge, there are 100 divisions on the circular scale and the main scale moves by $0.5\text{ mm}$ on a complete rotation of the circular scale. The zero of circular scale lies 6 divisions below the line of graduation when two studs are brought in contact with each other. When a wire is placed between the studs, 4 linear scale divisions are clearly visible while $46$th division the circular scale coincide with the reference line. The diameter of the wire is ______________ $\times 10^{-2}\text{ mm}$.

In Young's double slit experiment, two slits $S_1$ and $S_2$ are '$d$' distance apart and the separation from slits to screen is $D$ (as shown in figure). Now if two transparent slabs of equal thickness $0.1\text{ mm}$ but refractive index $1.51$ and $1.55$ are introduced in the path of beam $(\lambda = 4000\ \text{\AA}$) from $S_1$ and $S_2$ respectively. The central bright fringe spot will shift by ___________ number of fringes.