List of top Physics Questions

Escape velocity for 'a projectile at Earth's surface is v,. A body is projected from earth's surface with velocity $2v_e$. The velocity of the body when it is at infinite distance from the centre of the Earth is

The insulation property of air breakdown is $3 \times 10^6 V/m$. Maximum charge in coulomb that can be given to a sphere of radius 10 cm is approximately

An electron projected in a perpendicular uniform magnetic field of $3 \times 10^{-3} T, $ moves in a circle of radius 4 mm. The linear momentum of electron $(in \, kg-ms^{-1}) $ is

In series L-C-R circuit, the capacitance is changed from C to 2C. The inductance should be changed from L to ... to obtain same resonance frequency.

The condition for a uniform spherical mass $m$ of radius $r$ to be a black hole is : $[G=$ gravitational constant and $g=$ acceleration due to gravity]

From the top of a tower of two stones, whose masses are in the ratio $1 : 2$ are thrown on straight up with an initial speed $u$ and the second straight down with the same speed $u$. Then neglecting air resistance :

Electron of mass $m$ and charge $q$ is travelling with a speed $v$ along a circular path of radius $r$ at right angles to a uniform magnetic field of intensity $B$. If the speed of the electron is doubled and the magnetic field is halved the resulting path would have a radius:

The induction coil works on the principle of :

If a liquid does not wet glass, its angle of contact is :

An electron moves at right angle to a magnetic field of $1.5 \times 10^{-2} T$ with a speed of $6 \times 10^{7} m / s$. If the specific charge of the electron is $1.7 \times 10^{11} C / kg$. The radius of the circular nath will he

The work done in carrying a charge $q$ once round a circle of radius $r$ with a charge $Q$ at the centre is :

In a circuit L, C and R are connected in series with an alternating voltage source of frequency f .The current leads the voltage by 45$^{\circ}$. The value of C is

The wave theory of light, in its original form, was first postulated by-

In Young's double slit experiment intensity at a point is (1/4) of the maximum intensity. Angular position of this point is

A sphere of diameter $0.2\,m$ and mass $2\, kg$ is rolling on an inclined plane with velocity $ \upsilon =0.5\, m/s$. The kinetic energy of the sphere is:

A circular coil of $20$ turns and radius $10 \,cm$ is placed in uniform magnetic field of $ 0.10\,T $ normal to the plane of the coil. If the current in coil is $5 \,A$, then the torque acting on the coil will be

An automobile travelling at 50 km/h, can be stopped at a distance of 40 m by applying brakes. If the same automobile is travelling at 90 km/h, all other conditions remaining same and assuming no skidding, the minimum stopping distance in metres is:

An ideal gas is taken from point $ A $ to the point $ B $ , as shown in the $ p-V $ diagram, keeping the temperature constant. The work done in the process is :

The angular resolution of a 10 cm diameter telescope at a wavelength of 5000 $\mathring{A}$ is of the order of

If a vector 2î+3ĵ+8 is perpendicular to the vector 4ĵ-4î+α,then the value of α is:

Two uniform metal rods of lengths $ {{l}_{1}} $ and $ {{l}_{2}} $ and linear coefficients of expansion $ {{\alpha }_{1}} $ and $ {{\alpha }_{2}} $ respectively are connected to form a single rod of length $ ({{l}_{1}}+{{l}_{2}}). $ When the temperature of the combined rod is raised by t ?C, the length of each rod increases by the same amount. Then $ \left( \frac{{{\alpha }_{2}}}{{{\alpha }_{1}}+{{\alpha }_{2}}} \right) $ is:

A rifle shoots a bullet with a muzzle velocity of $ 500\,m{{s}^{-1}} $ at a small target 50 m away. To hit the target the rifle must be aimed: (Take $ g=10\,m{{s}^{-2}} $ )

A rigid container with thermally insulated walls contains a coil of resistance 100 $\Omega$, carrying current 1 A. Change in internal energy after 5 min will be

In an experiment with sonometer a tuning fork of frequency $256\, Hz$ resonates with a length of $25\, cm$ and another tuning fork resonates with a length of $16\, cm$. Tension of the string remaining constant the frequency of the second tuning fork is :

The ratio of velocity of sound in hydrogen and oxygen at STP is :