List of top Physics Questions

A small object is placed $50\, cm$ to the left of a thin convex lens of focal length $30\, cm$. A convex spherical mirror of radius of curvature $100\, cm$ is placed to the right of the lens at a distance $50\, cm$. The mirror is tilted such that the axis of the mirror is at an angle $\theta=30^{\circ}$ to the axis of the lens, as shown in the figure. If the origin of the coordinate system is taken to be at the centre of the lens, the coordinates (in $cm$ ) of the point $(x, y)$ at which the image is formed are

A gas under constant pressure of $ 45 \times 10^5\, p_a $ when subjected to $ 800 \,k j $ of heat, changes the volume from $ 0.5\, m^3 $ to $ 2.0\, m^3 $ . The change in internal energy of the gas is

A force $F = 75\, N$ is applied on a block of mass $5\, kg$ along the fixed smooth incline as shown in figure. Here gravitational acceleration $g = 10m/s^2$. The acceleration of the block is

A particle enters uniform constant magnetic field region with its initial velocity parallel to the field direction. Which of the following statements about its velocity is correct? (neglect the effects of other fields)

A cell has terminal voltage $2\, V$ in open circuit and internal resistance of the given cell is $2O$. If $4\, A$ of current is flowing between points $P$ and $Q$ in the circuit and then the potential difference between $P$ and $Q$ is

The $rms$ value of current in a $50 \,Hz$ $AC$ circuit is $6\,A$. The average value of $AC$ current over a cycle is

Ozone layer block the radiation of wavelength

A string fixed at both ends has a standing wave mode for which the distances between adjacent nodes is $18\, cm$. For the next consecutive standing wave mode distances between adjacent nodes is $16\, cm$. The minimum possible length of the string is

A small bead of mass $M$ slides on a smooth wire that is bent in a circle of radius $R$. It is released at the top of the circular part of the wire (point A in the figure) with a negligibly small velocity. Find the height H where the bead will reverse direction.

A Proton and an alpha particle both are accelerated through the same potential difference. The ratio of corresponding de-Broglie wavelengths is

A particle is moving in translatory motion. If momentum of the particle decreases by $10\%$, kinetic energy will decrease by

The two coherent sources with intensity ratio $\beta$ produce interference. The fringe visibility will be

The substance magnetite is

The stress-strain graph of a material is shown in the figure. The region in which the material is elastic is

The self inductance of a long solenoid carrying current is independent of

The intensity ratio of the maxima and minima in an interference pattern produced by two coherent sources of light is 9 : 1. The intensities of the used light sources are in ratio

The freezing point of a solution containing 0.2 g of acetic acid in 20.0 g benzene is lowered by 0.45 $^{\circ}$C. The degree of association of acetic acid in benzene is (Assume acetic acid dimerises in benzene and $K_f$ for benzene = $5.12\, K \,kg \,mol^{-1}$) $M_{observed}$ of acetic acid = 113.78

The energy stored in a parallel plate capacitor of cross section area $ A $ with a separation $ d $ being filled with dielectric of dielectric constant $ \varepsilon_{0} $ in terms of the electric field between them, $ E $ is

The emergent ray of light after refraction at a rectangular glass slab

The electric field strength in $N \,C\,^{-1}$ that is required to just prevent a water drop carrying a charge $1.6 \times 10^{-19} \, C$ from falling under gravity is $(g\, = \,9.8\, ms^{-2}$, mass of water drop = $0.0016\,g$)

Light wave enters from medium $1$ to medium $2$. Its velocity in $2^{nd}$ medium is double from $1^{st}$. For total internal reflection the angle of incidence must be greater than

If the linear momentum is increased by $50\%$, then kinetic energy will increase by

Consider the system shown in figure. The pulley and the string are light and all the surfaces are frictionless. The tension in the string is (take g = 10 m s)

When an object is placed between two plane parallel mirrors, then all the images found are of equal intensity. In case of plane parallel mirrors, only two images are possible.

Value of radius of gyration of a uniform rigid body depends on axis of rotation. Radius of gyration is root mean square distance of particles of the body from the axis of rotation.