List of top Physics Questions

In an experiment using Young?s double slit, what will be the value of fringe width $ \beta $ , if the wavelength is doubled?
The length of a second?s pendulum at the surface of earth is 1 m. The length of second?s pendulum at the surface of moon where g is 1/6th that at earth?s surface is
The length of a metal wire is l When the tension in it is T and is l when the tension is T. The natural length of the wire is
Lenz law is based in principle of conservation of:
In YDSE angular fringe width is 0.1 rad wavelength of light used is 6000 $?$. Find distance between two slits.
Find the correct diagram of electric lines of forces for negative charge -
At what height above the earth?s surface, the value of $g$ is half of its value on earth?s surface? Given its radius is 6400 km.
A horizontal pipe line carries water in a streamline flow. At a point along the pipe where the crosssectional area is 10 cm, the water velocity is 1 ms and the pressure is 2000 Pa. What is the pressure at another point where the crosssectional area is 5 cm?
A frictionless wire AB is fixed on a sphere of radius R. A very small spherical ball slips on this wire. The time taken by this ball to slip from A to B is
Two identical thin plano-convex glass lenses (refractive index 1.5) each having radius of curvature of 20 cm are placed with their convex surfaces in contact at the centre. The intervening space is filled with oil of refractive index 1.7. The focal length of the combination is
Find the position of final image from first lens.If the focal length of each lens is 10 cm.
The phenomenon involved in the reflection of radio-waves by ionosphere is similar to
A toroid has 500 turns per metre length. If it carries a current of 2A, the magnetic energy density inside the toroid is
A thermodynamic system undergoes a cyclic process ABC as shown in the diagram. The work done by the system per cycle is
A Point object is moving uniformly towards the pole of a concave mirror of focal length 25 cm along its axis as shown below. The speed of the object is 1 $ms^{-1}$. At t = 0, the distance of the object from the mirror is 50 cm. The average velocity of the image formed by the mirror between time t = 0 and t = 0.25 s is
During inelastic collision between two bodies, which of the following quantities always remain conserved?
Ionized hydrogen atoms and $\alpha$-particles with same momenta enters perpendicular to a constant magnetic field. B. The ratio of their radii of their paths $r_H : r_\alpha$ will be :
Body A of mass 4m moving with speed u collides with another body B of mass 2m, at rest. The collision is head on and elastic in nature. After the collision the fraction of energy lost by the colliding body A is :
A force F = 20 + 10y action a particle in y-direction where F is in newton and y in meter. Work done by this force to move the particle from y = 0 to y = 1 m is :
When an unpolarised beam of light of intensity $I_0$ is incident on a polaroid, the intensity of transmitted light is
?Lumen? is the unit of
Two beams of red and violet colour are made to pass separately through a prism with angle of prism $60^{\circ}$. In the position of minimum deviation, the angle of refraction will be:
A solution containing active cobalt $^{60}_{27}Co$ having activity of $0.8 \, \mu Ci$ and decay constant $\lambda$ is injected in an animal?s body. If $1 \, cm^3$ of blood is drawn from the animal?s body after 10 hrs of injection, the activity found was 300 decays per minute. What is the volume of blood that is flowing in the body ? ($1 \, Ci=3.7 \times 10^{10}$ decays per second and at $t=10 hrs e^{- \lambda t} =0.84$)
An unstable heavy nucleus at rest breaks into two nuclei which move away with velocities in the ratio of $8 : 27$. The ratio of the radii of the nuclei (assumed to be spherical) is :
A parallel plate capacitor of capacitance $90\, pF$ is connected to a battery of emf $20\, V$. If a dielectric material of dielectric constant $ K = \frac{5}{3} $ is inserted between the plates, the magnitude of the induced charge will be :