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A surface of side L metre in the plane of the paper is placed in a uniform electric field E (volt/m) acting along the same plane at an angle θ with the horizontal side of the square as shown in figure. The electric flux linked to the surface in unit of V-m, is
A monoatomic gas at pressure $p_1$ and volume $V_1$ is compressed adiabatically to $\frac{1}{8}^{\text{th}}$ its original volume. What is the final pressure of the gas?
An electron having charge e and mass m is moving in a uniform electric field E. Its acceleration will be:
The electric intensity due to an infinite cylinder of radius $R$ and having charge $q$ per unit length at a distance $r$ ($r > R$) from its axis is:
A wire loop is rotated in a magnetic field. The frequency of change of direction of the induced emf is:
An electron moves on a straight-line path XY as shown. The abcd is a coil adjacent to the path of the electron. What will be the direction of the current, if any, induced in the coil?
The second overtone of an open organ pipe has the same frequency as the first overtone of a closed pipe $L$ metre long. The length of the open pipe will be
An ideal gas undergoes four different processes from the same initial state as shown in the figure below. Those processes are adiabatic, isothermal, isobaric, and isochoric. The curve which represents the adiabatic process among $1$, $2$, $3$ and $4$ is:
The magnetic flux linked with a coil (in Wb) is given by the equation $\phi = 5t^2 + 3t + 60$. The magnitude of induced emf in the coil at $t = 4$ s will be:
Sound waves travel at $350 \text{ m/s}$ through warm air and at $3500 \text{ m/s}$ through brass. The wavelength of a $700 \text{ Hz}$ acoustic wave as it enters brass from warm air:
A conducting circular loop is placed in a uniform magnetic field $0.04\text{ T}$ with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at $2\text{ mm/s}$. The induced emf in the loop when the radius is $2\text{ cm}$ is:
An ideal gas goes from state $A$ to state $B$ via three different processes, as indicated in the $P$-$V$ diagram. If $Q_1, Q_2, Q_3$ indicates the heat absorbed by the gas along the three processes and $\Delta U_1, \Delta U_2, \Delta U_3$ indicates the change in internal energy along the three processes respectively, then:
A full wave rectifier circuit consists of two p-n junction diodes, a centre-tapped transformer, capacitor and a load resistance. Which of these components remove the ac ripple from the rectified output?
If c is the velocity of light in free space, the correct statements about photons among the following are: (A) The energy of a photon is E = hν. (B) The velocity of a photon is c. (C) The momentum of a photon, p = hν/c. (D) In a photon-electron collision, both total energy and total momentum are conserved. (E) Photon possesses a positive electric charge.
Two waves are represented by the equations $y_1=a\sin(\omega t+kx+0.57)\text{ m}$ and $y_2=a\cos(\omega t+kx)\text{ m}$, where $x$ is in metre and $t$ in second. The phase difference between them is:
A siren emitting a sound of frequency $800\text{ Hz}$ moves away from an observer towards a cliff at a speed of $15\text{ ms}^{-1}$. The frequency of sound that the observer hears in the echo reflected from the cliff will be: (Take, velocity of sound in air = $330\text{ ms}^{-1}$)
Planck's constant has the dimensions (unit) of
A source of unknown frequency gives $4 \text{ beats/s}$ when sounded with a source of known frequency $250 \text{ Hz}$. The second harmonic of the source of unknown frequency gives five beats per second when sounded with a source of frequency $513 \text{ Hz}$. The unknown frequency is
The current $i$ in a coil varies with time as shown in the figure. The variation of induced emf with time would be:
A transverse wave is represented by $y=A\sin(\omega t-kx)$. For what value of the wavelength is the wave velocity equal to the maximum particle velocity?