List of top Physics Questions

Sinusoidal carrier voltage of frequency $1.5\, MHz$ and amplitude $50\, V$ is amplitude modulated by sinusoidal voltage of frequency $10\, kHz$ producing $50 \%$ modulation. The lower and upper side-band frequencies in $kHz$ are

The collector plate in an experiment on photoelectric effect is kept vertically above the emitter plate. Light source is put on and a saturation photo-current is recorded. An electric field is switched on which has a vertically downward direction, then

In the hydrogen atom, the electron is making $6.6 \times 10^{15}$ rps. If the radius of orbit is $0.53 \times 10^{-10}$ m, then magnetic field produced at the centre of the orbit is

Hot water cools from $60^{\circ}C$ to $50^{\circ}C$ in the first $10$ minutes and to $42^{\circ}C$ in the next $10$ minutes. Then the temperature of the surroundings is

For detecting intensity of light we use

The Young's modulus of brass and steel are respectively $ 1.0\times 10^{11}Nm^{-2} $ and $ 2.0\times 10^{11}Nm^{-2}. $ .A brass wire and a steel wire of the same length are extended by $1 \,mm$ each under the same force. If radii of brass and steel wires are $R_B$ and $R_S$ respectively, then

The equivalent resistance across A and B is

The forbidden energy gap in $Ge$ is $0.72\, eV$. Given, $hc = 12400 \, eV \, - ?$ . The maximum wavelength of radiation that will generate an electron hole pair is

$\mu_0$ and $\varepsilon_0$ denote the permeability and permittivity of free space, the dimensions of $\mu_0 \varepsilon_0$ are

For any two vectors A and B, if $A\cdot B =|A \times B |$ , the magnitude of C = A + B is equal to

A solid cylinder and a hollow cylinder, both of the same mass and same external diameter are released from the same height at the same time on an inclined plane. Both roll down without slipping. Which one will reach the bottom first?

A gramophone record is revolving with an angular velocity $\omega$. A coin is placed at a distance $r$ from the centre of the record. The static coefficient of friction is $\mu$. The coin will revolve with the record if

The set which represents the isotope, isobar and isotone respectively is

The ratios of the distance traversed, in successive intervals of time by a body, falling from rest, are

The temperature of a gas contained in a closed vessel of constant volume increases by $1^\circ$C when the pressure of the gas is increased by $1\%$. The initial temperature of the gas is ..........

Two smalI spheres of masses $M_1 $ and $M_2$ are suspended by weightless insulating threads of lengths $ L_1$ and $ L_2$. The spheres carry charges $Q_1$ and $Q_2$ respectively. The spheres are suspended such that they are in level with one another and the threads are inclined to the vertical at angles of $\theta_1 $ and $\theta_2$ as shown. Which one of the following conditions is essential, if $\theta_1 = \theta_2$ ?

There is a uniform electric field of intensity $E$ which is as shown. How many labelled points have the same electric potential as the fully shaded point?

For measurement of potential difference, potentiometer is preferred in comparison to voltmeter because

In a parallel plate capacitor, the capacity increases if

Which of the following relation is true?

The equation of a simple harmonic progressive wave is given by $ y = A \,sin \,(100\, \pi t - 3x) $ . Find the distance between $ 2 $ particles having a phase difference of $ \frac{\pi}{3} $ .

The binding energy per nucleon, for nuclei with atomic mass number $A > 100$ decreases with $A$. The nuclear forces are weak for heavier nuclei.

With an increase in temperature, surface tension of liquid (except molten copper and cadmium)

The increase in pressure required to decrease the $ 200 \,L $ volume of a liquid by $ 0.008\% $ in $ kPa $ is (Bulk modulus of the liquid $ = 2100 \,MPa $ is)

For an opaque body coefficient of transmission is