List of top Physics Questions

Two long parallel wires are at a distance $2d$ apart. They carry steady equal current flowing out of the plane of the paper as shown. The variation of the magnetic field $B$ along the line $XX'$ is given by
A liquid is kept in a cylindrical vessel which is being rotated about a vertical axis through the centre of the circular base. If the radius of the vessel is $r$ and angular velocity of rotation is $\omega$, then the difference in the heights of the liquid at the centre of the vessel and the edge is
A hydrogen atom emits a photon corresponding to an electron transition from $n=5$ to $n=1$. The recoil speed of hydrogen atom is almost (mass of proton $\approx 1.6 \times 10^{-27} \,kg$ )
The power factor of an $R-L$ circuit is $ \frac{ 1}{ \sqrt 2} $ . If the frequency of AC is doubled, what will be the power factor?
A galvanometer of resistance $ 15O $ gives full scale deflection for a current of $2\, mA$. Calculate the shunt resistance needed to convert it into an ammeter of range $5\,A$
A cyclist rides up a hill at a constant velocity. Determine the power developed by the cyclist if the length of the connecting rod of the pedal is $r = 25 \,cm$, the time of revolution of the rod is $t = 2 \,s$ and the mean force exerted by his foot on the pedal is $F = 15\, kgf$.
Generally the path of a projectile from the earth is parabolic but it is elliptical for projectile going to a very large height. Up to ordinary height the projectile moves under a uniform gravitational force, but for great heights, projectile moves under a variable force.
One-fourth length of a spring of force constant k is cut away. The force constant of the remaining spring will be
If $E=at+bt^2, $ what is the neutral temperature?
The output form of a full wave rectifier is
A capillary tube of radius $r$ is immersed in water and water rises in it to a height $h$. The mass of water in the capillary tube is $5\,g$. Another capillary tube of radius $2\,r$ is immersed in water. The mass of water that will rise in this tube is
A bullet of mass $m$ moving with velocity $v$ strikes a suspended wooden block of mass $M$. If the block rises to a $S$ height the initial velocity of the block will be
A body falls freely from the top of a tower. It covers $36\%$ of the total height in the last second before striking the ground level. The height of the tower is
The fundamental frequency of a closed pipe is $220 \,Hz$. If $\frac{1}{4}$ of the pipe is filled with water, the frequency of the first overtone of the pipe now is
A winding wire which is used to frame a solenoid can bear a maximum $10\, A$ current. If length of solenoid is $80\, cm$ and its cross-sectional radius is $3\, cm$ then required length of winding wire is $(B=0.2\, T)$
A battery is connected to a uniform resistance wire $AB$ and $B$ is earthed. Which one of the graphs below shows how the current density $J $ varies along $AB$?
An inductor $ L,\,\,a $ capacitor of $ 20\mu F $ and a resistor of $ 10\Omega $ are connected in series with an $AC$ source of frequency $ 50\,Hz $ . If the current is in phase with the voltage, then the inductance of the inductor 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}}) $
In an $ AC $ circuit the potential difference V and current i are given respectively by $ V=100\sin (100t) $volt and $ i=100\sin \left( 100t+\frac{\pi }{3} \right)mA $ The power dissipated in the circuit will be
A particle is moving with velocity $\vec{v} = k\left(y\hat{i} + x\hat{j}\right),$ where $k$ is a constant. The general equation for its path is
A block of mass $10\, kg$ is moving in $x$-direction with a constant speed of $10\, m / s$. It is subjected to a retarding force $F=-0.1 \times J / m$ during its travel from $x=20\, m$ to $x=30\, m$. Its final kinetic energy will be :
A $12\, HP$ motor has to be operated $8\, h /$ day. How much will it cost at the rate of $50$ paise/kWh in 10 days?
When an ideal monoatomic gas is heated at consant pressure, fraction of heat energy supplied which increases the internal energy of gas, is
A body of mass $m$ rises to a height $h=\frac{R}{5}$ from the earth's surface where $R$ is earth's radius. If $g$ is acceleration due to gravity at the earth's surface, the increase in potential energy will be
The ratio of the dimensions of Plancks constant and that of the moment of inertia is the dimensions of