List of top Physics Questions

A uniform chain of length $L$ and mass $M$ is lying on a smooth table and one third of its length is hanging vertically down over the edge of the table. If $g$ is acceleration due to gravity, work required to pull the hanging part on to the table is
A rectangular loop carrying a current i is situated near a long straight wire such that the wire is parallel to one of the sides of the loop and is in the plane of the loop. If steady current I is established in the wire as shown in the figure, the loop will
White light is used to illuminate the two slits in a Young's double slit experiment. The separation between the slits is b and the screen is at a distance d (>> b) from the slits. At a point on the screen directly in front of one of the slits, certain wavelengths are missing. Some of these missing wavelengths are
$L, C$ and $R$ represent the physical quantities inductance, capacitance and resistance respectively. The combinations which have the dimensions of frequency are
A box is moved along a straight line by a machine delivering constant power. The distance moved by the body in time $t$ is proportional to
A solid conducting sphere having a charge Q is surrounded by an uncharged concentric conducting hollow spherical shell. Let the potential difference between the surface of the solid sphere and that of the outer surface of the hollow shell be V. If the shell is now given a change of - 3Q, the new potential difference between the same two surfaces is
A ray of light from a denser medium strikes a rarer medium at an angle of incidence i (see figure). The reflected and refracted rays make an angle of $90^\circ$ with each other. The angles of reflection and refraction are r and r'. The critical angle is
The equation; \(4\space _1^1H \rightarrow _4^2{He}^2+2e^-+26 MeV\)
The current i in the circuit (see figure) is
A hollow metal sphere of radius 5 cm is charged such that the potential on its surface is 10 V. The potential at the centre of the sphere is.
Beta rays emitted by a radioactive material are
An ideal monoatomic gas is taken round the cycle $ABCDA$ as shown in the P - V diagram (see figure). The work done during the cycle is
A thin circular ring of mass M and radius r is rotating about its axis with a constant angular velocity $\omega$. Two objects, each of mass m, are attached gently to the opposite ends of a diameter of the ring. The wheel now rotates with an angular velocity
A conducting circular loop of radius r carries a constant current i . It is placed in a uniform magnetic field $B_0$ such that $B_0$ is perpendicular to the plane of the loop. The magnetic force acting on the loop is
If elements with principal quantum number $n > 4$ were not allowed in nature, the number of possible elements would be
Consider the spectral line resulting from the transition $n=2\rightarrow n=1$ in the atoms and ions given below. The shortest wavelength is produced by
Two particles which are initially at rest, move towards each other under the action of their internal attraction. If their speeds are $v$ and $2v$ at any instant, then the speed of centre of mass of the system will be
A convex lens of focal length 40 cm is in contact with a concave lens of focal length 25 cm. The power of the combination is
The threshold wavelength for photoelectric emission from a material is $5200\mathring{A}$. Photoelectrons will be emitted when this material is illuminated with monochromatic radiation from a
In the Young's double slit experiment, the interference pattern is found to have an intensity ratio between the bright and dark fringes as 9, This implies that
In the arrangement shown in the figure, the ends P and Q of an unstretchable string move downwards with uniform speed U. Pulleys A and B are fixed. Mass M moves upwards with a speed
A particle is moving eastwards with a velocity of $5\, m / s$. In $10\, s$ the velocity changes to $5\, m / s$ northwards. The average acceleration in this time is
The plate resistance of a triode is $3 \times 10^3 \Omega$ and its mutual conductance is $1.5 \times 10^{-3} A/V$. The amplification factor of the triode is
A glass prism of refractive index 1.5 is immersed in water (refractive index 4/3). A light beam incident normally on the face AB is totally reflected to reach the face BC if
An alpha particle of energy $5 \,MeV$ is scattered through $180^\circ$ by a fixed uranium nucleus. The distance of closest approach is of the order of