List of top Physics Questions

Two parallel plates have equal and opposite charge. When the space between them is evacuated, the electric field between the plates is $ 2 \times 10^5 \, Vm^{ - 1}$. When the space is filled with dielectric thel electric field becomes $1 \times 10^5 Vm^{ -1}$ . The dielectric constant of dielectric material is
Two identical long conducting wires $AOB$ and $COD$ are placed at right angle to each other, with one above other such that $O$ is their common point for the two. The wires carry $I_1$ and $I_2$ currents, respectively. Point $P$ is lying at distance $d$ from $O$ along a direction perpendicular to the plane containing the wires. The magnetic field at the point $P$ will be
Two boys are standing at the ends $A$ and $B$ of a ground, where $A B=a$. The boy at $B$ starts running in a direction perpendicular to $A B$ with velocity $v_{1}$. The boy at $A$ starts running simultaneously with velocity $v$ and catches the other boy in a time $t$, where $t$ is
Three capacitors each of capacity $4\, \mu F$ are to be connected in such a way that the effective capacitance is $ 6 \,\mu F$ This can be done by
The unit of permittivity of free space, $ {{\varepsilon }_{0}}, $ is
300 J of work is done in sliding a 2 kg block up an inclined plane of height 10 m. Taking $ g=10\,m/{{s}^{2}}, $ the work done against friction is
Dopplers effect in sound takes place when source and observer arc
The tension in vibrating streched piano wire is 10 N. To double the frequency, the tension in wire must be
The threshold wavelength for a metal having work function $ W_0 $ is $\lambda_0 $. What is the threshold wavelength for a metal whose work function is $ \frac{ W_0 }{ 2 } $ ?
the power factor of a series L-C-R circuit when at resonance is
The phase difference between the instantaneous velocity and acceleration of a particle executing simple harmonic motion is
The period of oscillation of a simple pendulum of constant length al surface of the earth is $T$. Its time period inside a mine will be
The peak voltage in the output of a half-wave diode rectifier fed with a sinusoidal signal without filter is $10\, V$. The DC component of the output voltage is
The moment of inertia of a thin uniform circular disc about one of the diameters is $l$. Its moment of inertia about an axis perpendicular to the plane of the disc and passing through its centre is
The maximum intensity of fringes in Youngs experiment is $I$. If one of the slit is closed then the intensity at that place becomes $I_{0}$ . Which of the following relation is true?
The limiting friction is
The intensity of sound increases at night due to
The driver of a car travelling at velocity $v$ suddenly sees a broad wall in front of him at a distance $d$. He should
The displacement of an object attached to a spring and executing simple harmonic motion is given by $x = 2 ??10^{-2}\, cos\, \pi t$ metres. The time at which the maximum speed first occurs is
The dimensions of $\frac{e^{2}}{4 \pi \varepsilon_{0} h c'}$, where $e, \varepsilon_{0}, h$ and $c$ and $c$ are electronic charge, electric permittivity Planck's constant and velocity of light in vacuum respectively
The dimensions of universal gravitational constant are
The degrees of freedom of a molecule of a triatomic gas are
The capacity of an isolated conducting sphere of radius $R$ is proportional to
On introducing a thin film in the path of one of the two interfering beams, the central fringe will shift by one fringe width. If $ \mu =1.5, $ the thickness of the film is (wavelength of monochromatic light is $ \lambda $ )
Moment of inertia of ring about its diameter is $ I. $ Then, moment of inertia about an axis passing through centre perpendicular to its plane is