List of top Physics Questions

A large number of particles are placed around the origin, each at a distance $R$ from the origin. The distance of the center of mass of the system from the origin is
The rms speed of oxygen is $v$ at a particular temperature. If the temperature is doubled and oxygen molecules dissociate into oxygen atoms, the rms speed becomes
A radiation of energy 'E ' falls normally on a perfectly reflecting surface. The momentum transferred to the surface is (C = Velocity of light)
The length of a metal wire is $L_1$ when the tension is $T_1$ and $L_2$ when the tension is $T_2$. The unstretched length of the wire is
A simple pendulum of length $L$ swings in a vertical plane. The tension of the string when it makes an angle $\theta$ with the vertical and the bob of mass m moves with a speed $v$ is ($g$ is the gravitational acceleration
A potentiometer wire has length 4 m and resistance $8\, \Omega.$ The resistance that must be connected in series with the wire and an accumulator of e.m.f. 2 V, so as to get a potential gradient 1 mV per cm on the wire is
If potential (in volts) in a region is expressed as $V(x, y , z)$ = $6xy - y + 2yz$, the electric field $(in\, N/C)$ at point $(1, 1, 0)$ is
A stretched string is vibrating in the second overtone, then the number of nodes and anti nodes between the ends of the string are respectively
Two particles $A$ and $B$ are moving as shown in the figure. Their total angular momentum about the point $O$ is
Two particles, $A$ and $B$, having equal charges, after being accelerated through the same potential difference enter into a region of uniform magnetic field and the particles describe circular paths of radii $R_{1}$ and $R_{2}$, respectively. The ratio of the masses of $A$ and $B$ is
A straight conductor $0.1\, m$ long moves in a uniform magnetic field $0.1\, T$. The velocity of the conductor is $15\, m / s$ and is directed perpendicular to the field. The emf induced between the two ends of the conductor is
A parallel plate capacitor is charged and then isolated. The effect of increasing the plate separation on charge, potential and capacitance respectively are
A coil of area $5 \, cm^2$ having $20$ turns is placed in a uniform magnetic field of $10^3$ gauss. The normal to the plane of coil makes an angle $30^{\circ}$ with the magnetic field. The flux through the coil is
$1$ g of ice is mixed with $1\, g$ of steam. At thermal equilibrium, the temperature of the mixture is
The electric potential at a point in free space due to charge $Q$ coulomb is $ Q \times 10^{11} $ volts. The electric field at that point is
An $LED$ is constructed from a $pn$ junction based on a certain semi-conducting material whose energy gap is $1.9\, eV$. Then the wavelength of the emitted light is
An aircraft with a wingspan of $40\, m$ flies with a speed of $1080\, km/hr$ in the eastward direction at a constant altitude in the northern hemisphere, where the vertical component of the earth's magnetic field $1.75 \times 10^{-5}$ $T$. Then the emf developed between the tips of the wings is
The average power dissipated in a pure inductor is
For a simple pendulum, a graph is plotted between its Kinetic Energy (KE) and Potential Energy (PE) against its displacement d. Which one of the following represents these correctly? (graphs are schematic and not drawn to scale)
When two tuning forks $A$ and $B$ are sounded together. $4$ beats per second are heard. The frequency of the fork $B$ is $384\, Hz$. When one of the prongs of the fork $A$ is filed and sounded with $B$. the beat frequency increases, then the frequency of the fork $A$ is
The ratio of kinetic energy to the potential energy of a particle executing $SHM$ at a distance equal to half its amplitude, the distance being measured from its equilibrium position is
Planck's constant h, speed of light c and gravitational constant G are used to form a unit of length L and a unit of mass M. Then the correct option(s) is(are)
Particle $A$ moves along $X$-axis with a uniform velocity of magnitude $10\, m / s$. Particle $B$ moves with uniform velocity $20\, m / s$ along a direction making an angle of $60^{\circ}$ with the positive direction of $X$-axis as shown in the figure. The relative velocity of $B$ with respect to that of $A$ is
Two pendulum oscillate with a constant phase difference of $45^{\circ}$ and same amplitude. If the maximum velocity of one of them is $v$ and that of other is $v+x$ then the value of $x$ will be
Light of wavelength 500 nm is incident on a metal with work function 2.28 eV. The de Broglie wavelength of the emitted electron is