List of top Physics Questions

An open U-tube contains mercury. When $11.2 \,cm$ of water is poured into one of the arms of the tube, how high does the mercury rise in the other arm form its initial level?
The escape velocity of a projectile on the earths surface is $ 11.2\,\,km{{s}^{-1}} $ . A body is projected out with thrice this speed. The speed of the body far away from the earth will be:
In the given figure the pulley is assumed massless and frictionless. If the friction force on the object of mass m is $ f $ , then its acceleration in terms of the force $F$ will be equal to:
A can is moving horizontally along a straight line with constant speed $30\, m/s$. A projectile is to be fired from the moving cart in such a way that it will return to the cart after the cart has moved $80 \,m$. At what speed (relative to the can) must the projectile be fired? (Takes $ =10\,m/{{s}^{2}} $ )
The magnetic field amplitude of an electromagnetic wave is $ 2\times {{10}^{-7}}T $ , Its electric field amplitude, if the wave is travelling in free space is:
In the first second of its flight, rocket ejects 1/60 of its mass with a velocity of $ 2400\,\,m{{s}^{-1}} $ . The acceleration of the rocket is:
A body starts from rest with an uniform acceleration. If its velocity after $n$ seconds is $v$, then its displacement in the last $2\,s$ is
In $LCR$ circuit $ {f = \frac{ 50 }{ \pi} \, Hz, V = 50 \, volt, R = 300 \, \Omega}$ . If $L = 1 \, H$ and $C = 20 \, \mu \, C$, then voltage across capacitor is
Which one has highest binding energy per nucleon?
A block of mass $10\, kg$ is placed on rough horizontal surface whose coefficient of friction is $0.5$. If a horizontal force of $100 \,N$ is applied on it, then acceleration of the block will be :-
A person sees clearly at a distance of 100 cm, then power of lens used to see object at 40 cm is
Which of the following statements is true for an n-type semiconductor?
The motion of a particle varies with time according to the relation $ y=a(\sin \omega t+\cos \omega t) $
The image of a small electric bulb fixed on the wall of a room is to be obtained on the opposite wall $4\, m$ away by means of a large convex lens. The maximum possible focal length of the lens required for this purpose will be:
If boiling point of water is $ 95{}^\circ F, $ what will be reduction at celsius scale?
Carbon, silicon and germanium have four valence electrons each. These are characterized valence and conduction bands separated by energy band gap respectively equal to $ {{(Eg)}_{C}},{{(Eg)}_{Si}} $ and $ {{(Eg)}_{Ge}} $ . Which of the following statements is true?
A body moves along a circular path of radius $10\, m$ and the coefficient of friction is $0.5$. What should be its angular speed in rad/s if it is not to slip from the surface? ( $ g=9.8\text{ }m{{s}^{-2}} $ )
A body is initially at rest. It undergoes one dimensional motion with constant acceleration. The power delivered to it at time $t$ is proportional to
lf the focal length of the lens is $20\, cm$. what is the distance of the image from the lens in the following figure?
The total energy of a satellite moving with an orbital velocity $v$ around the earth is
The speed of a wave on a string is $150\, ms^{-1}$ when the tension is $120\, N$. The percentage increase in the tension in order to raise the wave speed by $20\%$ is
A 0.5 kg ball moving with a speed of 12 $ms^{-1}$ strikes a hard wall at an angle of 30$^{\circ}$ with the wall. It is reflected with the same speed and at the same angle. If the ball is in contact with the wall for 0.25 s, the average force acting on the wall is :-
Two copper wires of length $ l $ and $2 l $ have radii $r$ and $2r$ respectively. What is the ratio of their specific resistances?
Principle of $H$-bomb is:
What is dimensional formula of thermal conductivity?