List of top Physics Questions

Unpolarized light of intensity $I_0$ is incident on a polarizer and the emerging light strikes a second polarizing filter with its axis at 45$^\circ$ to that of the first. The intensity of the emerging beam
Units commonly used for measuring wavelength of light and distance between neutron and proton of an atom are
Unit of intensity of illumination is:
Unit of electrical conductivity is
Uniform magnetic field exists in region given by B=3i+4j+5k . A rod of length 5 m is placed along y - axis is moved along x axis with constant speed 1 m/sec. Then the magnitude of induced e.m.f in the rod is :
Two wires of equal length and cross-section are suspended as shown. Their Young?? modulii are $Y_1$ and $Y_2$ respectively. The equivalent Young?? modulus will be
Two wires of diameter 0.25 cm, one made of steel and the other made of brass are loaded as shown in figure. The unloaded length of steel wire is 1.5 m and that of brass wire is 1 m. $\left(Y_{Steel}=2\times10^{11}\,N\,m^{-2}, Y_{Brass}=1\times 10^{11}\,N\,m^{-2}\right)$
The ratio of elongations of the steel wire to that of brass wire is
Two vessels having equal volume contain molecular hydrogen at one atmosphere and helium at two atmospheres respectively . If both samples are at the same temperature ,the rms velocity of hydrogen molecules is :
Two waves having intensities in the ratio of 9 : 1 produce interference. The ratio of maximum to minimum intensity is equal to
Two waves are represented by the following equation $y_1-5 \sin\,2\pi(10t-0.1x)$ and $v_2=10 \sin\,2\pi(10t-0.1x).$ The ratio of intensities $\frac{I_2}{I_1}$ will be
Two vectors are perpendicular, if
Two vectors inclined at an angle $\theta$ have magnitude 3 N and 5 N and their resultant is of magnitude 4 N. The angle $\theta$ is
Two vectors $\vec{A}$ and $\vec{B}$ inclined at an angle $\theta$ have a resultant $\vec{R}$ which makes an angle $\alpha$ with $\vec{A}$ and angle $\beta$ with $\vec{B}$ . Let the magnitudes of the vectors $\vec{A}$, $\vec{B}$ and $\vec{R}$ be represented by $A$, $B$ and $R$ respectively. Which of the following relations is not correct?
Two towns $ A $ and $ B $ are connected by a regular bus service with a bus leaving in either direction every $ T $ minutes. A man cycling with a speed of $ 20 \,km\,h^{-1} $ in the direction $ A $ to $ B $ notices that a bus goes past him every $ 18 $ min in the direction of his motion, and every $ 6 $ min in the opposite direction. The period $ T $ of the bus service is
Two syringes of different cross section (without needle) filled with water are connected with a tightly fitted rubber tube filled with water. Diameters of the smaller piston and larger piston are $1 \,cm$ and $3\, cm$ respectively. If a force of $10\, N$ is applied to the smaller piston then the force exerted on the larger piston is , if the smaller piston is pushed in through $6 \,cm$, how much does the longer piston move out?
Two straight infinitely long and thin parallel wires are spaced 0.1 m apart and carry a current of 10A each. Find the magnetic field at a point distant 0.1 m from both wires when the currents are in the same direction.
Two spherical conductors A and B of radii 1 mm and 2mm are separated by a distance of 5 cm and are uniformly charged. If the spheres are connected by a conducting wire then in the equilibrium condition the ratio of electric fields at surfaces of A and B is
Two spheres each of mass $M$ and radius $R$ are separated by a distance of $r$. The gravitational potential at the midpoint of the line joining the centres of the spheres is
Two sources of light of wavelength $2500\, ? $ and $3500 \,? $ are used in Young?? double slit experiment simultaneously. Which orders of fringes of two wavelength patterns coincide?
Two slits are made one millimeter apart and the screen is placed one metre away. The fringe separation when blue green light of wavelength $500\, nm$ is used is
Two slits separated by a distance of 1 mm are illuminated with red light of wavelength $6.5 ? 10^{-7}\, m$. The interference fringes are observed on a screen placed 1 m from the slits. The distance between the third dark fringe and the fifth bright fringe is equal to
Two small spheres each carrying a charge $q$ are placed $1\,m$ apart. The electric force between them is $F$. If one sphere is taken around the other. The work done is :
Two short bar magnets with pole strengths of 900 ab-amp $\times$ cm and 100 ab-amp $\times$ cm are placed with their axes in the same vertical lines with similar poles facing each other. Each magnet has length of 1 cm. When the separation between the nearer poles is 1 cm. The weight of the.upper .magnet is supported by the repulsive force between the magnets. If g is 1000 $cm/sec^2$ the mass of the upper magnet is:
Two short magnets each of dipole moment M, are fastened perpendicularly at their centres. The magnitude of magnetic field at a distance d from the centre on the bisector of the right angle is
Two satellites of masses 400 kg, 500 kg are revolving around earth in different circular in defferent circular orbit of radii $r_1,r_2$ such that their kinetic energies are equal. The ratio of $r_1$ to $r_2$ is