List of top Physics Questions

Dimensions of planck's constant is equal to that of

The star appears blue, when its surface temperature is

Control rods used in nuclear reactors are made of

A particle is projected from the ground with an initial speed of v at an angle $\theta$ with horizontal. The average velocity of the particle between its point of projection and highest point of trajectory is

A car is travelling with a linear velocity $v$ on a circular road of radius $r$. If it is increasing its speed at the rate of $a m / s ^{2}$, then the resultant acceleration will be

A source and an observer are moving towards each other with a speed equal to $v/2$, where $v$ is the speed of sound. The source is emitting sound of frequency $n$. The frequency heard by one observer will be

The half-life of a radioactive substance is $10$ days. This means that

A prism is made up of material of refractive index $\sqrt{3}$. The angle of prism is $A$. If the angle of minimum deviation is equal to the angle of the prism, then the value of $A$ is

An alternating voltage V = $V_0 \sin \omega t$ is applied across a circuit. As result $I = I_0 \sin(\omega t - \pi /2)$ flows in it. The power consumed per cycle is

To double the covering range of a TV transmitter tower, its height should be made

1 curie is

The magnifying power of a compound microscope is high if

Sound waves do not show the phenomenon of

A boy of mass $m$ stands on one end of a wooden planck of length $L$ and mass $M$. The plank is floating on water. If the boy walks from one end of the plank to the other end at a constant speed, the resulting displacement of the plank is given by

Water is flowing in streamline motion through a horizontal tube. The pressure at a point in the tube is $p$ where the velocity of flow is $v$. At another point, where the pressure is $p/2$, the velocity of flow is [density of water = $?$]

Two non-conducting solid spheres of radii $R$ and $2R$ , having uniform volume charge densities $\rho _1 $ and $ \rho _2 $ respectively, touch each other. The net electric field at a distance $2R$ from the centre of the smaller sphere, along the line joining the centre of the spheres, is zero. The ratio $\rho _1 \, / \, \rho _2 $ can be

The work done on a particle of mass $m$ by a force $K \left[\frac{ x }{\left( x ^{2}+ y ^{2}\right)^{3 / 2}} \hat{ i }+\frac{ y }{\left( x ^{2}+ y ^{2}\right)^{3 / 2}} \hat{ j }\right]$ ( $K$ being a constant of appropriate dimensions, when the particle is taken from the point $( a , 0)$ to the point $(0, a )$ along a circular path of radius a about the origin in the $x$-y plane is

The ratio of the radii of the nuclei $ _{13}Al^{27} $ and $ _{52}Te^{125} $ is

The initial rate of hydrolysis of methyl acetate $(1 M)$ by a weak acid $(HA, 1M) $ is 1/100th of that of a strong acid $(HX, 1M)$, at $ 25^{\circ} C.$ The $ K_a ( H A ) $ is

The electric field in a region is given by $ E=\frac{A}{x^{3}}\,\hat{i}+By\,\hat{j}+Cz^{2}\,\hat{k} $ The $ SI $ units of $ A $ , $ B $ and $ C $ are, respectively

In a new system of units called star units, $ 1\,kg^* = 10 \,kg $ , $ 1 \,m^* =1 \,km $ and $ 1s^* = 1 $ minute, what will be the value of $ 1J $ in the new system ?

Figure shows a series $LCR$ circuit with $R = 200 \,\Omega,\, C = 15.0\, \mu F$ and $L = 230\, mH$. If $\varepsilon = 36.0\, sin\, 120\pi t$, the amplitude $I_{0}$ of the current $I$ in the circuit is close to

Figure gives the acceleration of a $2.0 \,kg$ body as it moves from rest along $x$ axis while a variable force acts on it from $ x=0\,m $ to $ x=9\,m $ . The work done by the force on the body when it reaches (i) $ x=4\,m $ and (ii) $ x=7\,m $ shall be as given below

An object and its real image are located at distances $25\, cm$ and $40 \,cm$ respectively from the two principal foci of a convex lens. The linear magnification of the image is near to

A uniform rope of mass $ 0.1 \,kg $ and length $ 2.45 \,m $ hangs from a ceiling. The time taken by a transverse wave to travel the full length of the rope is