List of top Physics Questions

What is the electric flux linked with closed surface ?
When a body is charged by induction, then the body
When a person combs his hair, static electricity is sometimes generated by what process?
Which of the following statements about dipole moment is not true?
Which of the following is best insulator ?
At what distance along the central axis of a uniformly charged plastic disc of radius R is the magnitude of the electric field equal to one-half the magnitude of the field at the centre of the surface of the disc?
A charge $q_1$ exerts some force on a second charge $q_2$. If third charge $q_3$ is brought near, the force of $q_1$ exerted on $q_2$
A charged particle of mass 0.003 g is held stationary in space by placing it in a downward direction of electric field of $ 6 \times 10^4$ N/C. Then the magnitude of charge is
A coin is made up of Al and weighs $0.75\,g$. It has a square shape and its diagonal measures $17\,mm$. It is electrically neutral and contains equal amounts of positive and negative charges. The magnitude of these charges is ( Atomic mass of Al $= 26.98\,g$)
A conducting sphere of radius $10\,cm$ has unknown charge. If the electric field at a distance $20\,cm$ from the centre of the sphere is $1.2 \times 10^3\, N\, C^{-1}$ and points radially inwards. The net charge on the sphere is
A cup contains $250\,g$ of water. Find the total positive charge present in the cup of water
A dielectric sphere is placed in a uniform electric field directed along the positive y-axis. Which one of the following represents the correct equipotential surface?
A dipole of electric dipole moment p is placed in a uniform electric field of strength E. If $\theta$ is the angle between positive directions of p and E, then the potential energy of the electric dipole is largest when $\theta$ is
A metallic spherical shell has an inner radius $R_1$ and outer radius $R_2$. A charge is placed at the centre of the spherical cavity, the surface charge density on the outer surface is
A point positive charge is brought near an isolated conducting sphere. The electric field is best given by
A positive charge $Q$ is uniformly distributed along a circular ring of radius $R$. A small test charge $q$ is placed at the centre of the ring as shown in figure. Then
Pick out the wrong statement (s) . (i) Vapour pressure of a liquid is the measure of the strength of intermolecular attractive forces. (ii) Surface tension of a liquid acts perpendicular to the surface of the liquid. (iii) Vapour pressure of all liquids is same at their freezing points. (iv) Liquids with stronger intermolecular attractive forces are more viscous than those with weaker intermolecular force.
Surface tension does not vary with
Surface tension of mercury is $ 0.465 \,N\, m^{-1} $ . The excess pressure inside a mercury drop of diameter $ 6 \,mm $ is
The speed $v$ of ripples on the surface of water depends on surface tension $ \sigma$ density p and wavelength $ \lambda $. The square of speed v is proportional to
The surface tension of a liquid at its boiling point is
The surface tension of a soap solution is $25 \times 10^{-3}\,N/m$. The excess pressure inside a soap bubble of diameter 1 cm is
Two soap bubbles of radii a and b combine to form a single bubble of radius 3) If P is the external pressure, then S.T. of the soap solutionis
A soap bubble of radius $r$ is blown up to form a bubble of radius $2 r$ under isothermal conditions. If $T$ is the surface tension of soap solution, the energy spent in the blowing
A spherical liquid drop of radius $R$ is divided into eight equal droplets. If surface tension is $T$, then work done in the process will be